Techniques for managing power on an uplink component carrier transmitted over a shared radio frequency spectrum band

ABSTRACT

Techniques are described for wireless communication. A first method includes identifying a first uplink component carrier of a plurality of component carriers configured for a user equipment (UE); determining that the first uplink component carrier is transmitted over a shared radio frequency spectrum band; and performing a power management operation on the first uplink component carrier, for a current subframe, based at least in part on the determining.

CROSS REFERENCES

The present application for patent claims priority to U.S. ProvisionalPatent Application No. 62/058,823 by Chen et al., titled “Techniques forManaging Power on an Uplink Component Carrier Transmitted Over a SharedRadio Frequency Spectrum Band,” filed Oct. 2, 2014, assigned to theassignee hereof, which is hereby incorporated by reference in itsentirety.

BACKGROUND Field of the Disclosure

The present disclosure, for example, relates to wireless communicationsystems, and more specifically to techniques for managing power on anuplink component carrier transmitted over a shared radio frequencyspectrum band.

Description of Related Art

Wireless communication systems are widely deployed to provide varioustypes of communication content such as voice, video, packet data,messaging, broadcast, and so on. These systems may be multiple-accesssystems capable of supporting communication with multiple users bysharing the available system resources (e.g., time, frequency, andpower). Examples of such multiple-access systems include code-divisionmultiple access (CDMA) systems, time-division multiple access (TDMA)systems, frequency-division multiple access (FDMA) systems,single-carrier frequency-division multiple access (SC-FDMA) systems, andorthogonal frequency-division multiple access (OFDMA) systems.

By way of example, a wireless multiple-access communication system mayinclude a number of base stations, each simultaneously supportingcommunication for multiple communication devices, otherwise known asuser equipments (UEs). A base station may communicate with UEs ondownlink channels (e.g., for transmissions from a base station to a UE)and uplink channels (e.g., for transmissions from a UE to a basestation).

Some modes of communication may enable communications between a basestation and a UE over a shared radio frequency spectrum band, or overdifferent radio frequency spectrum bands (e.g., a licensed radiofrequency spectrum band or a shared radio frequency spectrum band) of acellular network. With increasing data traffic in cellular networks thatuse a licensed radio frequency spectrum band, offloading of at leastsome data traffic to a shared radio frequency spectrum band may providea cellular operator with opportunities for enhanced data transmissioncapacity. A shared radio frequency spectrum band may also provideservice in areas where access to a licensed radio frequency spectrumband is unavailable.

Prior to gaining access to, and communicating over, a shared radiofrequency spectrum band, a base station or UE may perform a listenbefore talk (LBT) procedure to contend for access to the shared radiofrequency spectrum band. An LBT procedure may include performing a clearchannel assessment (CCA) procedure to determine whether a channel of theshared radio frequency spectrum band is available. When it is determinedthat the channel of the shared radio frequency spectrum band isavailable, a channel usage beacon signal (CUBS) may be transmitted toreserve the channel.

In some modes of operation, a UE may operate in a carrier aggregationmode or dual-connectivity mode, in which the UE may be configured tocommunicate with one or more base stations using a plurality ofcomponent carriers. When communicating using two or more componentcarriers, a UE may be allocated a transmit power per component carrier,as well as a total transmit power (e.g., a maximum transmit power forthe combination of component carriers in use). At times, the sum oftransmit powers of the various component carriers in use by the UE mayexceed the total transmit power. In these cases, the UE may employ powerscaling to bring the sum of transmit powers of the various componentcarriers to within the total transmit power.

SUMMARY

The present disclosure, for example, relates to one or more techniquesfor managing power on an uplink component carrier transmitted over ashared radio frequency spectrum band. Because the process of contendingfor access to a shared radio frequency spectrum band is uncertain (e.g.,winning access to the shared radio frequency spectrum band may not occuron a first attempt, or in every subframe in which contention for accessis attempted), it is useful to maintain access to the shared radiofrequency spectrum band as long as possible when there are transmissionsto be made. However, power management operations (e.g., power scalingtechniques) that have been designed for use on uplink component carrierstransmitted over a licensed radio frequency spectrum band when operatingin a carrier aggregation mode can result in a power reduction sosignificant that a transmission on a component carrier is dropped. Whena transmission is dropped, another transmitting apparatus may contendfor access to the shared radio frequency spectrum band and gain accessthereto, and prohibit the transmitting apparatus that dropped thetransmission from regaining access to the shared radio frequencyspectrum band. Power management operations that have been designed foruse on uplink component carriers transmitted over a licensed radiofrequency spectrum band when operating in a carrier aggregation mode canalso result in fluctuations in transmit power from one subframe toanother subframe, which can be undesirable when transmitting over ashared radio frequency spectrum band.

In an example, a method for wireless communication is described. In oneexample, the method includes determining whether a first uplinkcomponent carrier of a plurality of component carriers is configured fora UE; determining that the first uplink component carrier is transmittedover a shared radio frequency spectrum band; and performing a powermanagement operation on the first uplink component carrier, for acurrent subframe, based at least in part on the determining.

In some examples of the method, performing the power managementoperation may include maintaining a transmit power on the first uplinkcomponent carrier at or above a minimum guaranteed power. In someexamples, the minimum guaranteed power may depend on a channel type oruplink information type transmitted on the first uplink componentcarrier. In some examples, the method may include scheduling at leastone of a physical uplink control channel (PUCCH) or a physical uplinkshared channel (PUSCH) on the first uplink component carrier during thecurrent subframe. In some examples, the minimum guaranteed power mayinclude at least one of a PUCCH minimum guaranteed power component and aPUSCH minimum guaranteed power component, and the PUCCH minimumguaranteed power component may be greater than the PUSCH minimumguaranteed power component.

In some examples of the method, performing the power managementoperation may include scaling a transmit power on the first uplinkcomponent carrier to a reduced power for the current subframe. In someexamples, the method may include using the reduced power as a maximumtransmit power on the first uplink component carrier for at least onesubsequent subframe following the current subframe. In some examples,the at least one subsequent subframe may include at least one uplinksubframe between the current subframe and a boundary of a subsequentframe. In some examples, the method may include dropping a transmissionon the first uplink component carrier for at least one of a number ofuplink subframes between the current subframe and a boundary of asubsequent frame. In some examples, the scaling may surpass a thresholdpower reduction, and the method may include dropping a transmission onthe first uplink component carrier for at least one of a number ofuplink subframes between the current subframe and a boundary of asubsequent frame.

In some examples of the method, performing the power managementoperation may include using a transmit power on the first uplinkcomponent carrier during a subframe preceding the current subframe. Thetransmit power may be a maximum transmit power on the first uplinkcomponent carrier for the current subframe.

In some examples of the method, performing the power managementoperation may include dropping a transmission on the first uplinkcomponent carrier for the current subframe. In some examples, the methodmay include dropping a transmission on the first uplink componentcarrier for at least one of a number of uplink subframes between thecurrent subframe and a boundary of a subsequent frame. In some examples,the method may include dropping a transmission on the first uplinkcomponent carrier for at least one of a number of uplink subframesbetween the current subframe and a boundary of a subsequent frame. Insome examples, the method may include performing a CCA for the sharedradio frequency spectrum band. The CCA may be performed for at least onesubsequent uplink subframe following the current subframe.

In some examples, the method may include receiving a first uplinkscheduling for the first uplink component carrier for the currentsubframe, and receiving a second uplink scheduling for the first uplinkcomponent carrier for the current subframe. In some examples, the methodmay include using the second uplink scheduling based at least in part onperforming the power management operation. In some examples, the methodmay include using the first uplink scheduling or the second uplinkscheduling based at least in part on a condition of the power managementoperation. In some examples, performing the power management operationmay include scaling the transmit power on the first uplink componentcarrier to a reduced power for the current subframe, using the firstuplink scheduling when the scaling does not surpass a threshold powerreduction, and using the second uplink scheduling when the scalingsurpasses the threshold power reduction.

In some examples of the method, the plurality of component carriers mayinclude a second uplink component carrier transmitted over the sharedradio frequency spectrum band. In some examples of the method, theplurality of component carriers may include a second uplink componentcarrier transmitted over a licensed radio frequency spectrum band. Insome examples of the method, the plurality of component carriers may beconfigured for a carrier aggregation operation for the UE. In someexamples of the method, the plurality of component carriers may beconfigured for a dual-connectivity operation for the UE.

In an example, an apparatus for wireless communication is described. Inone example, the apparatus may include means for identifying a firstuplink component carrier of a plurality of component carriers configuredfor a UE; means for determining that the first uplink component carrieris transmitted over a shared radio frequency spectrum band; and meansfor performing a power management operation on the first uplinkcomponent carrier, for a current subframe, based at least in part on thedetermining.

In an example, another apparatus for wireless communication isdescribed. In one example, the apparatus may include a processor andmemory in electronic communication with the processor. The processor andthe memory may be configured to identify a first uplink componentcarrier of a plurality of component carriers configured for a UE;determine that the first uplink component carrier is transmitted over ashared radio frequency spectrum band; and perform a power managementoperation on the first uplink component carrier, for a current subframe,based at least in part on the determining.

In some examples, the apparatus may maintain transmit power on the firstuplink component. In some examples, the minimum guaranteed power dependson a channel type or uplink information type transmitted on the firstuplink component carrier. In some examples, the apparatus may scale atransmit power on the first uplink component carrier to a reduced powerfor the current subframe. In some examples, the apparatus may use thereduced power as a maximum transmit power on the first uplink componentcarrier for at least one subsequent subframe following the currentsubframe.

In an example, a non-transitory computer-readable medium storingcomputer-executable code for wireless communication is described. In oneexample, the code may be executable by a processor to identify a firstuplink component carrier of a plurality of component carriers configuredfor a UE; determine that the first uplink component carrier istransmitted over a shared radio frequency spectrum band; and perform apower management operation on the first uplink component carrier, for acurrent subframe, based at least in part on the determining. In someexamples, the code may also be used to implement one or more aspects ofthe method for wireless communication described above with respect tothe first set of illustrative examples.

The foregoing has outlined rather broadly the features and technicaladvantages of examples according to the disclosure in order that thedetailed description that follows may be better understood. Additionalfeatures and advantages will be described hereinafter. The conceptionand specific examples disclosed may be readily utilized as a basis formodifying or designing other structures for carrying out the samepurposes of the present disclosure. Such equivalent constructions do notdepart from the scope of the appended claims. Characteristics of theconcepts disclosed herein, both their organization and method ofoperation, together with associated advantages will be better understoodfrom the following description when considered in connection with theaccompanying figures. Each of the figures is provided for the purpose ofillustration and description, and not as a definition of the limits ofthe claims.

BRIEF DESCRIPTION OF THE DRAWINGS

A further understanding of the nature and advantages of the presentinvention may be realized by reference to the following drawings. In theappended figures, similar components or features may have the samereference label. Further, various components of the same type may bedistinguished by following the reference label by a dash and a secondlabel that distinguishes among the similar components. If only the firstreference label is used in the specification, the description isapplicable to any one of the similar components having the same firstreference label irrespective of the second reference label.

FIG. 1 illustrates an example of a wireless communication system, inaccordance with various aspects of the present disclosure;

FIG. 2 shows a wireless communication system in which LTE/LTE-A may bedeployed under different scenarios using a shared radio frequencyspectrum band, in accordance with various aspects of the presentdisclosure;

FIG. 3 shows a wireless communication system in which LTE/LTE-A may bedeployed in a carrier aggregation scenario, in accordance with variousaspects of the present disclosure;

FIG. 4 shows a wireless communication system in which LTE/LTE-A may bedeployed in a dual-connectivity scenario, in accordance with variousaspects of the present disclosure;

FIG. 5 shows an example of a wireless communication over a shared radiofrequency spectrum band, in accordance with various aspects of thepresent disclosure;

FIG. 6 shows a block diagram of an apparatus for use in wirelesscommunication, in accordance with various aspects of the presentdisclosure;

FIG. 7 shows a block diagram of an apparatus for use in wirelesscommunication, in accordance with various aspects of the presentdisclosure;

FIG. 8 shows a block diagram of a UE for use in wireless communication,in accordance with various aspects of the present disclosure;

FIG. 9 shows a block diagram of a base station (e.g., a base stationforming part or all of an eNB) for use in wireless communication, inaccordance with various aspects of the present disclosure;

FIG. 10 is a block diagram of a multiple input/multiple output (MIMO)communication system including a base station and a UE, in accordancewith various aspects of the present disclosure;

FIG. 11 is a flow chart illustrating an example of a method for wirelesscommunication, in accordance with various aspects of the presentdisclosure;

FIG. 12 is a flow chart illustrating an example of a method for wirelesscommunication, in accordance with various aspects of the presentdisclosure;

FIG. 13 is a flow chart illustrating an example of a method for wirelesscommunication, in accordance with various aspects of the presentdisclosure;

FIG. 14 is a flow chart illustrating an example of a method for wirelesscommunication, in accordance with various aspects of the presentdisclosure; and

FIG. 15 is a flow chart illustrating an example of a method for wirelesscommunication, in accordance with various aspects of the presentdisclosure.

DETAILED DESCRIPTION

Techniques are described in which a shared radio frequency spectrum bandis used for at least a portion of communications over a wirelesscommunication system. In some examples, the shared radio frequencyspectrum band may be used for Long Term Evolution (LTE) communicationsor LTE-Advanced (LTE-A) communications. The shared radio frequencyspectrum band may be used in combination with, or independent from, alicensed radio frequency spectrum band. In some examples, the sharedradio frequency spectrum band may be a radio frequency spectrum band forwhich a device may need to contend for access because the radiofrequency spectrum band is available, at least in part, for unlicenseduse, such as Wi-Fi use.

With increasing data traffic in cellular networks that use a licensedradio frequency spectrum band, offloading of at least some data trafficto a shared radio frequency spectrum band may provide a cellularoperator (e.g., an operator of a public land mobile network (PLMN) or acoordinated set of base stations defining a cellular network, such as anLTE/LTE-A network) with opportunities for enhanced data transmissioncapacity. Use of a shared radio frequency spectrum band may also provideservice in areas where access to a licensed radio frequency spectrumband is unavailable. As noted above, before communicating over a sharedradio frequency spectrum band, transmitting apparatuses may perform anLBT procedure to gain access to the medium. Such an LBT procedure mayinclude performing a CCA procedure (or extended CCA procedure) todetermine whether a channel of the shared radio frequency spectrum bandis available. When it is determined that the channel of the shared radiofrequency spectrum band is available, a CUBS may be transmitted toreserve the channel. When it is determined that a channel is notavailable, a CCA procedure (or extended CCA procedure) may be performedfor the channel again at a later time.

After winning contention for access to a shared radio frequency spectrumband, it may be desirable for a UE to maintain access to the sharedradio frequency spectrum band for a duration of a prescribed time inwhich a transmission is to be made. When the UE loses access to theshared radio frequency spectrum band, there can be uncertainty as towhen the UE may regain access to the shared radio frequency spectrumband. Power management operations currently used on uplink componentcarriers in an LTE/LTE-A network, when operating in a carrieraggregation mode, can sometimes result in a power scaling and/or otherpower management operation that leads to a transmission on an uplinkcomponent carrier being dropped. Because power scaling may beprioritized, with power preservation on an uplink component carriercarrying a physical uplink control channel (PUCCH) being givenpreference over power preservation on a component carrier carrying aphysical uplink shared channel (PUSCH) with uplink control information(UCI), and with power preservation on an uplink component carriercarrying a PUSCH with UCI being given preference over power preservationon an uplink component carrier carrying a PUSCH without UCI,transmissions on some uplink component carriers are more at risk ofbeing dropped than others. When operating in a dual-connectivity mode ofoperation over an LTE/LTE-A network, groups of component carriersassociated with different base stations may be configured withrespective minimum guaranteed transmit powers, with some amount ofresidual transmit power being sharable among the different groups ofuplink component carriers. This can provide connectivity to each of thebase stations. However, power scaling may once again be prioritizedamong individual component carriers, with power preservation on acomponent carrier carrying an acknowledgement (ACK), non-acknowledgement(NAK), or scheduling request (SR) being given preference over powerpreservation on an uplink component carrier carrying channel stateinformation (CSI), and with power preservation on an uplink componentcarrier carrying CSI being given preference over power preservation onan uplink component that does not carry UCI. Again, transmissions onsome uplink component carriers are more at risk of being dropped.

In an LTE/LTE-A network using a shared radio frequency spectrum band, itmay be useful to mitigate the frequency of dropped transmissions, sothat access to the shared radio frequency spectrum band does not have tobe reacquired. It may also be useful to maintain a constant transmitpower on the shared radio frequency spectrum band, and/or to change thetransmit power on the shared radio frequency spectrum band in acontrolled and steady manner.

The following description provides examples, and is not limiting of thescope, applicability, or examples set forth in the claims. Changes maybe made in the function and arrangement of elements discussed withoutdeparting from the scope of the disclosure. Various examples may omit,substitute, or add various procedures or components as appropriate. Forinstance, the methods described may be performed in an order differentfrom that described, and various steps may be added, omitted, orcombined. Also, features described with respect to some examples may becombined in other examples.

FIG. 1 illustrates an example of a wireless communication system 100, inaccordance with various aspects of the present disclosure. The wirelesscommunication system 100 may include base stations 105, UEs 115, and acore network 130. The core network 130 may provide user authentication,access authorization, tracking, Internet Protocol (IP) connectivity, andother access, routing, or mobility functions. The base stations 105 mayinterface with the core network 130 through backhaul links 132 (e.g.,S1, etc.) and may perform radio configuration and scheduling forcommunication with the UEs 115, or may operate under the control of abase station controller (not shown). In various examples, the basestations 105 may communicate, either directly or indirectly (e.g.,through core network 130), with each other over backhaul links 134(e.g., X1, etc.), which may be wired or wireless communication links.

The base stations 105 may wirelessly communicate with the UEs 115 viaone or more base station antennas. Each of the base station 105 sitesmay provide communication coverage for a respective geographic coveragearea 110. In some examples, a base station 105 may be referred to as abase transceiver station, a radio base station, an access point, a radiotransceiver, a NodeB, an eNodeB (eNB), a Home NodeB, a Home eNodeB, orsome other suitable terminology. The geographic coverage area 110 for abase station 105 may be divided into sectors making up a portion of thecoverage area (not shown). The wireless communication system 100 mayinclude base stations 105 of different types (e.g., macro or small cellbase stations). There may be overlapping geographic coverage areas 110for different technologies.

In some examples, the wireless communication system 100 may include anLTE/LTE-A network. In LTE/LTE-A networks, the term evolved Node B (eNB)may be used to describe the base stations 105, while the term UE may beused to describe the UEs 115. The wireless communication system 100 maybe a Heterogeneous LTE/LTE-A network in which different types of eNBsprovide coverage for various geographical regions. For example, each eNBor base station 105 may provide communication coverage for a macro cell,a small cell, or other types of cell. The term “cell” is a 3GPP termthat can be used to describe a base station, a carrier or componentcarrier associated with a base station, or a coverage area (e.g.,sector, etc.) of a carrier or base station, depending on context.

A macro cell may cover a relatively large geographic area (e.g., severalkilometers in radius) and may allow unrestricted access by UEs withservice subscriptions with the network provider. A small cell may be alower-powered base station, as compared with a macro cell that mayoperate in the same or different (e.g., licensed, shared, etc.) radiofrequency spectrum bands as macro cells. Small cells may include picocells, femto cells, and micro cells according to various examples. Apico cell may cover a relatively smaller geographic area and may allowunrestricted access by UEs with service subscriptions with the networkprovider. A femto cell also may cover a relatively small geographic area(e.g., a home) and may provide restricted access by UEs having anassociation with the femto cell (e.g., UEs in a closed subscriber group(CSG), UEs for users in the home, and the like). An eNB for a macro cellmay be referred to as a macro eNB. An eNB for a small cell may bereferred to as a small cell eNB, a pico eNB, a femto eNB or a home eNB.An eNB may support one or multiple (e.g., two, three, four, and thelike) cells (e.g., component carriers).

The wireless communication system 100 may support synchronous orasynchronous operation. For synchronous operation, the base stations mayhave similar frame timing, and transmissions from different basestations may be approximately aligned in time. For asynchronousoperation, the base stations may have different frame timing, andtransmissions from different base stations may not be aligned in time.The techniques described herein may be used for either synchronous orasynchronous operations.

The communication networks that may accommodate some of the variousdisclosed examples may be packet-based networks that operate accordingto a layered protocol stack. In the user plane, communications at thebearer or Packet Data Convergence Protocol (PDCP) layer may be IP-based.A Radio Link Control (RLC) layer may perform packet segmentation andreassembly to communicate over logical channels. A Medium Access Control(MAC) layer may perform priority handling and multiplexing of logicalchannels into transport channels. The MAC layer may also use Hybrid ARQ(HARD) to provide retransmission at the MAC layer to improve linkefficiency. In the control plane, the Radio Resource Control (RRC)protocol layer may provide establishment, configuration, and maintenanceof an RRC connection between a UE 115 and the base stations 105 or corenetwork 130 supporting radio bearers for the user plane data. At thePhysical (PHY) layer, the transport channels may be mapped to Physicalchannels.

The UEs 115 may be dispersed throughout the wireless communicationsystem 100, and each UE 115 may be stationary or mobile. A UE 115 mayalso include or be referred to by those skilled in the art as a mobilestation, a subscriber station, a mobile unit, a subscriber unit, awireless unit, a remote unit, a mobile device, a wireless device, awireless communications device, a remote device, a mobile subscriberstation, an access terminal, a mobile terminal, a wireless terminal, aremote terminal, a handset, a user agent, a mobile client, a client, orsome other suitable terminology. A UE 115 may be a cellular phone, apersonal digital assistant (PDA), a wireless modem, a wirelesscommunication device, a handheld device, a tablet computer, a laptopcomputer, a cordless phone, a wireless local loop (WLL) station, or thelike. A UE may be able to communicate with various types of basestations and network equipment, including macro eNBs, small cell eNBs,relay base stations, and the like.

The communication links 125 shown in wireless communication system 100may include downlink (DL) transmissions, from a base station 105 to a UE115, or uplink (UL) transmissions, from a UE 115 to a base station 105.The downlink transmissions may also be called forward linktransmissions, while the uplink transmissions may also be called reverselink transmissions. In some examples, UL transmissions may includetransmissions of uplink control information, which uplink controlinformation may be transmitted over an uplink control channel (e.g., aphysical uplink control channel (PUCCH) or enhanced PUCCH (ePUCCH)). Theuplink control information may include, for example, acknowledgements ornon-acknowledgements of downlink transmissions, or channel stateinformation. UL transmissions may also include transmissions of data,which data may be transmitted over a physical uplink shared channel(PUSCH) or enhanced PUSCH (ePUSCH). UL transmissions may also includethe transmission of a sounding reference signal (SRS) or enhanced SRS(eSRS), a physical random access channel (PRACH) or enhanced PRACH(ePRACH) (e.g., in the standalone mode described with reference to FIG.2 or the dual connectivity mode described with reference to FIG. 4), ora scheduling request (SR) or enhanced SR (eSR) (e.g., in the standalonemode described with reference to FIG. 2). References in this disclosureto a PUCCH, a PUSCH, a PRACH, an SRS, or an SR are presumed toinherently include references to a respective ePUCCH, ePUSCH, ePRACH,eSRS, or eSR.

In some examples, each communication link 125 may include one or morecarriers, where each carrier may be a signal made up of multiplesub-carriers (e.g., waveform signals of different frequencies) modulatedaccording to the various radio technologies described above. Eachmodulated signal may be sent on a different sub-carrier and may carrycontrol information (e.g., reference signals, control channels, etc.),overhead information, user data, etc. The communication links 125 maytransmit bidirectional communications using a frequency domain duplexing(FDD) operation (e.g., using paired spectrum resources) or a time domainduplexing (TDD) operation (e.g., using unpaired spectrum resources).Frame structures for FDD operation (e.g., frame structure type 1) andTDD operation (e.g., frame structure type 2) may be defined.

In some examples of the wireless communication system 100, base stations105 or UEs 115 may include multiple antennas for employing antennadiversity schemes to improve communication quality and reliabilitybetween base stations 105 and UEs 115. Additionally or alternatively,base stations 105 or UEs 115 may employ multiple-input, multiple-output(MIMO) techniques that may take advantage of multi-path environments totransmit multiple spatial layers carrying the same or different codeddata.

The wireless communication system 100 may support operation on multiplecells or carriers, a feature which may be referred to as carrieraggregation (CA) or dual-connectivity operation. A carrier may also bereferred to as a component carrier (CC), a layer, a channel, etc. Theterms “carrier,” “component carrier,” “cell,” and “channel” may be usedinterchangeably herein. A UE 115 may be configured with multipledownlink CCs and one or more uplink CCs for carrier aggregation. Carrieraggregation may be used with both FDD and TDD component carriers.

In an LTE/LTE-A network, a UE 115 may be configured to communicate usingup to five component carriers when operating in a carrier aggregationmode or dual-connectivity mode. When communicating using two or morecomponent carriers, a UE 115 may be allocated a transmit power percomponent carrier, as well as a total transmit power (e.g., a maximumtransmit power for the combination of component carriers in use). Attimes, the sum of transmit powers of the various component carriers inuse may exceed the total transmit power. In these cases, a UE 115 mayemploy power scaling to bring the sum of transmit powers of the variouscomponent carriers in use to within the total transmit power.

In some examples, the wireless communication system 100 may supportoperation over a licensed radio frequency spectrum band (e.g., a radiofrequency spectrum band for which transmitting apparatuses may notcontend for access because the radio frequency spectrum band is licensedto specific users for specific uses, such as a licensed radio frequencyspectrum band usable for LTE/LTE-A communications) or a shared radiofrequency spectrum band (e.g., a radio frequency spectrum band for whichtransmitting apparatuses may need to contend for access because theradio frequency spectrum band is available for unlicensed use, such asWi-Fi use). Upon winning a contention for access to the shared radiofrequency spectrum band, a transmitting apparatus (e.g., a base station105 or UE 115) may transmit one or more CUBS over the shared radiofrequency spectrum band. The CUBS may reserve the shared radio frequencyspectrum by providing a detectable energy on the shared radio frequencyspectrum band. The CUBS may also serve to identify the transmittingapparatus or serve to synchronize the transmitting apparatus and areceiving apparatus. In some examples, a CUBS transmission may commenceat a symbol period boundary (e.g., an OFDM symbol period boundary). Inother examples, a CUBS transmission may commence between symbol periodboundaries. In these latter examples, the transmission of a portion of aCUBS, which portion of a CUBS has a length that is shorter than a fullsymbol period, may provide a non-orthogonal transmission that interfereswith one or more transmissions on adjacent tones (e.g., one or moretransmissions of other apparatuses on adjacent tones).

FIG. 2 shows a wireless communication system 200 in which LTE/LTE-A maybe deployed under different scenarios using a shared radio frequencyspectrum band, in accordance with various aspects of the presentdisclosure. More specifically, FIG. 2 illustrates examples of asupplemental downlink mode (also referred to as a shared downlink mode),a carrier aggregation mode, and a standalone mode in which LTE/LTE-A isdeployed using a shared radio frequency spectrum band. The wirelesscommunication system 200 may be an example of portions of the wirelesscommunication system 100 described with reference to FIG. 1. Moreover, afirst base station 205 and a second base station 205-a may be examplesof aspects of one or more of the base stations 105 described withreference to FIG. 1, while a first UE 215, a second UE 215-a, a third UE215-b, and a fourth UE 215-c may be examples of aspects of one or moreof the UEs 115 described with reference to FIG. 1.

In the example of a supplemental downlink mode in the wirelesscommunication system 200, the first base station 205 may transmit OFDMAwaveforms to the first UE 215 using a downlink channel 220. The downlinkchannel 220 may be associated with a frequency F1 in a shared radiofrequency spectrum band. The first base station 205 may transmit OFDMAwaveforms to the first UE 215 using a first bidirectional link 225 andmay receive SC-FDMA waveforms from the first UE 215 using the firstbidirectional link 225. The first bidirectional link 225 may beassociated with a frequency F4 in a licensed radio frequency spectrumband. The downlink channel 220 in the shared radio frequency spectrumband and the first bidirectional link 225 in the licensed radiofrequency spectrum band may operate contemporaneously. The downlinkchannel 220 may provide a downlink capacity offload for the first basestation 205. In some examples, the downlink channel 220 may be used forunicast services (e.g., addressed to one UE) or for multicast services(e.g., addressed to several UEs). This scenario may occur with anyservice provider (e.g., a mobile network operator (MNO)) that uses alicensed radio frequency spectrum and needs to relieve some of thetraffic or signaling congestion.

In one example of a carrier aggregation mode in the wirelesscommunication system 200, the first base station 205 may transmit OFDMAwaveforms to the second UE 215-a using a second bidirectional link 230and may receive OFDMA waveforms, SC-FDMA waveforms, or resource blockinterleaved FDMA waveforms from the second UE 215-a using the secondbidirectional link 230. The second bidirectional link 230 may beassociated with the frequency F1 in the shared radio frequency spectrumband. The first base station 205 may also transmit OFDMA waveforms tothe second UE 215-a using a third bidirectional link 235 and may receiveSC-FDMA waveforms from the second UE 215-a using the third bidirectionallink 235. The third bidirectional link 235 may be associated with afrequency F2 in a licensed radio frequency spectrum band. The secondbidirectional link 230 may provide a downlink and uplink capacityoffload for the first base station 205. Like the supplemental downlinkdescribed above, this scenario may occur with any service provider(e.g., MNO) that uses a licensed radio frequency spectrum and needs torelieve some of the traffic or signaling congestion.

In another example of a carrier aggregation mode in the wirelesscommunication system 200, the first base station 205 may transmit OFDMAwaveforms to the third UE 215-b using a fourth bidirectional link 240and may receive OFDMA waveforms, SC-FDMA waveforms, or resource blockinterleaved waveforms from the third UE 215-b using the fourthbidirectional link 240. The fourth bidirectional link 240 may beassociated with a frequency F3 in the shared radio frequency spectrumband. The first base station 205 may also transmit OFDMA waveforms tothe third UE 215-b using a fifth bidirectional link 245 and may receiveSC-FDMA waveforms from the third UE 215-b using the fifth bidirectionallink 245. The fifth bidirectional link 245 may be associated with thefrequency F2 in the licensed radio frequency spectrum band. The fourthbidirectional link 240 may provide a downlink and uplink capacityoffload for the first base station 205. This example and those providedabove are presented for illustrative purposes and there may be othersimilar modes of operation or deployment scenarios that combineLTE/LTE-A in a licensed radio frequency spectrum band and use a sharedradio frequency spectrum band for capacity offload.

As described above, one type of service provider that may benefit fromthe capacity offload offered by using LTE/LTE-A in a shared radiofrequency spectrum band is a traditional MNO having access rights to anLTE/LTE-A licensed radio frequency spectrum band. For these serviceproviders, an operational example may include a bootstrapped mode (e.g.,supplemental downlink, carrier aggregation) that uses the LTE/LTE-Aprimary component carrier (PCC) on the licensed radio frequency spectrumband and at least one secondary component carrier (SCC) on the sharedradio frequency spectrum band.

In the carrier aggregation mode, data and control may, for example, becommunicated in the licensed radio frequency spectrum band (e.g., viafirst bidirectional link 225, third bidirectional link 235, and fifthbidirectional link 245) while data may, for example, be communicated inthe shared radio frequency spectrum band (e.g., via second bidirectionallink 230 and fourth bidirectional link 240). The carrier aggregationmechanisms supported when using a shared radio frequency spectrum bandmay fall under a hybrid frequency division duplexing-time divisionduplexing (FDD-TDD) carrier aggregation or a TDD-TDD carrier aggregationwith different symmetry across component carriers.

In one example of a standalone mode in the wireless communication system200, the second base station 205-a may transmit OFDMA waveforms to thefourth UE 215-c using a bidirectional link 250 and may receive OFDMAwaveforms, SC-FDMA waveforms, or resource block interleaved FDMAwaveforms from the fourth UE 215-c using the bidirectional link 250. Thebidirectional link 250 may be associated with the frequency F3 in theshared radio frequency spectrum band. The standalone mode may be used innon-traditional wireless access scenarios, such as in-stadium access(e.g., unicast, multicast). An example of a type of service provider forthis mode of operation may be a stadium owner, cable company, eventhost, hotel, enterprise, or large corporation that does not have accessto a licensed radio frequency spectrum band.

FIG. 3 shows a wireless communication system 300 in which LTE/LTE-A maybe deployed in a carrier aggregation scenario, in accordance withvarious aspects of the present disclosure. The wireless communicationsystem 300 may be an example of portions of the wireless communicationsystem 100 or 200 described with reference to FIG. 1 or 2. Moreover, abase station 305 may be an example of aspects of one or more of the basestations 105, 204, or 205-a described with reference to FIG. 1 or 2,while a UE 315 may be an examples of aspects of one or more of the UEs115, 215, 215-a, 215-b, or 215-c described with reference to FIG. 1 or2.

When communicating in a carrier aggregation mode using LTE/LTE-Acommunications, the UE 315 may communicate with the base station 305using up to five component carriers. One of the component carriers maybe designated as a primary component carrier, and the remainingcomponent carriers may be designated as secondary component carriers.Each component carrier may be configured as a downlink componentcarrier, an uplink component carrier, or a cell (e.g., a componentcarrier that may be configured for use as a downlink component carrierand/or an uplink component carrier). By way of example, FIG. 3illustrates communication between the UE 315 and the base station 305over five component carriers, including a first downlink componentcarrier 320, a second downlink component carrier 325, a third downlinkcomponent carrier 330, a first uplink component carrier 335, and asecond uplink component carrier 340. Each of the first downlinkcomponent carrier 320, the second downlink component carrier 325, thethird downlink component carrier 330, the first uplink component carrier335, and the second uplink component carrier 340 may operate in alicensed radio frequency spectrum band or a shared radio frequencyspectrum band, depending on how the component carrier is allocated orconfigured.

When the UE 315 is configured for operation in a supplemental downlinkmode of operation using a shared radio frequency spectrum band, asdescribed with reference to FIG. 2, and when the UE 315 is operating ina carrier aggregation mode, one or more of the first downlink componentcarrier 320, the second downlink component carrier 325, and the thirddownlink component carrier 330 may operate in the licensed radiofrequency spectrum band; one or more of the first downlink componentcarrier 320, the second downlink component carrier 325, and the thirddownlink component carrier 330 may operate in the shared radio frequencyspectrum band; and the first uplink component carrier 335 and the seconduplink component carrier 340 may operate in the licensed radio frequencyspectrum band.

When the UE 315 is configured for operation in a carrier aggregationmode of operation using the shared radio frequency spectrum band, asdescribed with reference to FIG. 2, one or more of the first downlinkcomponent carrier 320, the second downlink component carrier 325, andthe third downlink component carrier 330 may operate in the licensedradio frequency spectrum band; one or more of the first downlinkcomponent carrier 320, the second downlink component carrier 325, andthe third downlink component carrier 330 may operate in the shared radiofrequency spectrum band; one or more of the first uplink componentcarrier 335 and the second uplink component carrier 340 may operate inthe licensed radio frequency spectrum band; and one or more of the firstuplink component carrier 335 and the second uplink component carrier 340may operate in the shared radio frequency spectrum band. In someexamples, all of the downlink component carriers may operate in thelicensed radio frequency spectrum band, or all of the uplink componentcarriers may operate in the shared radio frequency spectrum band, butnot all of the downlink component carriers and all of the uplinkcomponent carriers may operate in the shared radio frequency spectrumband (e.g., at least one downlink component carrier or at least oneuplink component carrier operates in the licensed radio frequencyspectrum band).

When the UE 315 is configured for operation in a standalone mode ofoperation using the shared radio frequency spectrum band, as describedwith reference to FIG. 2, and when the UE 315 is operating in a carrieraggregation mode, all of the first downlink component carrier 320, thesecond downlink component carrier 325, the third downlink componentcarrier 330, the first uplink component carrier 335, and the seconduplink component carrier 340 may operate in the shared radio frequencyspectrum band.

FIG. 4 shows a wireless communication system 400 in which LTE/LTE-A maybe deployed in a dual-connectivity scenario, in accordance with variousaspects of the present disclosure. The wireless communication system 400may be an example of portions of the wireless communication system 100,200, or 300 described with reference to FIG. 1, 2, or 3. Moreover, afirst base station 405 and a second base station 405-a may be examplesof aspects of one or more of the base stations 105, 204, 205-a, or 305described with reference to FIG. 1 or 2, while a UE 415 may be anexamples of aspects of one or more of the UEs 115, 215, 215-a, 215-b,215-c, or 315 described with reference to FIG. 1, 2, or 3.

When communicating in a dual-connectivity mode using LTE/LTE-Acommunications, the UE 415 may communicate with multiple base stations,such as the first base station 405 and the second base station 405-a,using up to five component carriers. One of the component carriers maybe designated as a primary component carrier, and the remainingcomponent carriers may be designated as secondary component carriers.Each component carrier may be configured as a downlink componentcarrier, an uplink component carrier, or a cell (e.g., a componentcarrier that may be configured for use as a downlink component carrierand/or an uplink component carrier). By way of example, FIG. 4illustrates communication between the UE 415 and the base station 405over three component carriers, including a first component carrier 420,a second component carrier 425, and a third component carrier 430. Thefirst component carrier 420, the second component carrier 425, and thethird component carrier 430 may be configured for various modes ofoperation using a licensed radio frequency spectrum band or a sharedradio frequency spectrum band, similarly to how component carriers maybe used in a carrier aggregation mode of operation, as described, forexample, with reference to FIG. 3.

In some examples, a transmitting apparatus such as one of the basestations 105, 205, 205-a, 305, 405, or 405-a described with reference toFIG. 1, 2, 3, or 4, or one of the UEs 115, 215, 215-a, 215-b, 215-c,315, or 415 described with reference to FIG. 1, 2, 3, or 4, may use agating interval to gain access to a channel of a shared radio frequencyspectrum band (e.g., to a physical channel of the shared radio frequencyspectrum band). In some examples, the gating interval may be periodic.For example, the periodic gating interval may be synchronized with atleast one boundary of an LTE/LTE-A radio interval. The gating intervalmay define the application of a contention-based protocol, such as anLBT protocol based on the LBT protocol specified in EuropeanTelecommunications Standards Institute (ETSI) (EN 301 893). When using agating interval that defines the application of an LBT protocol, thegating interval may indicate when a transmitting apparatus needs toperform a contention procedure (e.g., an LBT procedure) such as a clearchannel assessment (CCA) procedure. The outcome of the CCA procedure mayindicate to the transmitting apparatus whether a channel of a sharedradio frequency spectrum band is available or in use for the gatinginterval (also referred to as an LBT radio frame). When a CCA procedureindicates that the channel is available for a corresponding LBT radioframe (e.g., “clear” for use), the transmitting apparatus may reserve oruse the channel of the shared radio frequency spectrum band during partor all of the LBT radio frame. When the CCA procedure indicates that thechannel is not available (e.g., that the channel is in use or reservedby another transmitting apparatus), the transmitting apparatus may beprevented from using the channel during the LBT radio frame.

FIG. 5 shows an example 500 of a wireless communication 510 over ashared radio frequency spectrum band, in accordance with various aspectsof the present disclosure. In some examples, the wireless communication510 may include a transmission of one or more uplink component carriers,which uplink component carrier(s) may be transmitted, for example, aspart of a transmission made according to the supplemental downlink mode,the carrier aggregation mode, or the standalone mode described withreference to FIG. 2, the carrier aggregation mode described withreference to FIG. 3, and/or the dual-connectivity mode described withreferenced to FIG. 4.

In some examples, an LBT radio frame 515 of the wireless communication510 may have a duration of ten milliseconds and include a number ofdownlink (D) subframes 520, a number of uplink (U) subframes 525, andtwo types of special subframes, an S subframe 530 and an S′ subframe535. The S subframe 530 may provide a transition between downlinksubframes 520 and uplink subframes 525, while the S′ subframe 535 mayprovide a transition between uplink subframes 525 and downlink subframes520 and, in some examples, a transition between LBT radio frames.

During the S′ subframe 535, a downlink clear channel assessment (DCCA)procedure 545 may be performed by one or more base stations, such as oneor more of the base stations 105, 205, or 205-a described with referenceto FIG. 1 or 2, to reserve, for a period of time, a channel of theshared radio frequency spectrum band over which the wirelesscommunication 510 occurs. Following a successful DCCA procedure 545 by abase station, the base station may transmit a channel usage beaconsignal (CUBS) (e.g., a downlink CUBS (D-CUBS 550)) to provide anindication to other base stations or apparatuses (e.g., UEs, Wi-Fiaccess points, etc.) that the base station has reserved the channel. Insome examples, a D-CUBS 550 may be transmitted using a plurality ofinterleaved resource blocks. Transmitting a D-CUBS 550 in this mannermay enable the D-CUBS 550 to occupy at least some percentage of theavailable frequency bandwidth of the shared radio frequency spectrumband and satisfy one or more regulatory requirements (e.g., arequirement that transmissions over the shared radio frequency spectrumband occupy at least 80% of the available frequency bandwidth). TheD-CUBS 550 may in some examples take a form similar to that of anLTE/LTE-A CRS or a channel state information reference signal (CSI-RS).When the DCCA procedure 545 fails, the D-CUBS 550 may not betransmitted.

The S′ subframe 535 may include a plurality of OFDM symbol periods(e.g., 14 OFDM symbol periods). A first portion of the S′ subframe 535may be used by a number of UEs as a shortened uplink (U) period. Asecond portion of the S′ subframe 535 may be used for the DCCA procedure545. A third portion of the S′ subframe 535 may be used by one or morebase stations that successfully contend for access to the channel of theshared radio frequency spectrum band to transmit the D-CUBS 550.

During the S subframe 530, an uplink CCA (UCCA) procedure 565 may beperformed by one or more UEs, such as one or more of the UEs 115, 215,215-a, 215-b, or 215-c described above with reference to FIG. 1 or 2, toreserve, for a period of time, the channel over which the wirelesscommunication 510 occurs. Following a successful UCCA procedure 565 by aUE, the UE may transmit an uplink CUBS (U-CUBS 570) to provide anindication to other UEs or apparatuses (e.g., base stations, Wi-Fiaccess points, etc.) that the UE has reserved the channel. In someexamples, a U-CUBS 570 may be transmitted using a plurality ofinterleaved resource blocks. Transmitting a U-CUBS 570 in this mannermay enable the U-CUBS 570 to occupy at least some percentage of theavailable frequency bandwidth of the shared radio frequency spectrumband and satisfy one or more regulatory requirements (e.g., therequirement that transmissions over the shared radio frequency spectrumband occupy at least 80% of the available frequency bandwidth). TheU-CUBS 570 may in some examples take a form similar to that of anLTE/LTE-A CRS or CSI-RS. When the UCCA procedure 565 fails, the U-CUBS570 may not be transmitted.

The S subframe 530 may include a plurality of OFDM symbol periods (e.g.,14 OFDM symbol periods). A first portion of the S subframe 530 may beused by a number of base stations as a shortened downlink (D) period555. A second portion of the S subframe 530 may be used as a guardperiod (GP) 560. A third portion of the S subframe 530 may be used forthe UCCA procedure 565. A fourth portion of the S subframe 530 may beused by one or more UEs that successfully contend for access to thechannel of the shared radio frequency spectrum band as an uplink pilottime slot (UpPTS) or to transmit the U-CUBS 570.

In some examples, the DCCA procedure 545 or the UCCA procedure 565 mayinclude the performance of a single CCA procedure. In other examples,the DCCA procedure 545 or the UCCA procedure 565 may include theperformance of an extended CCA procedure. The extended CCA procedure mayinclude a random number of CCA procedures, and in some examples mayinclude a plurality of CCA procedures.

When the wireless communication 510 includes a transmission of one ormore uplink component carriers according to a carrier aggregation modeof operation, scenarios may arise in which a power management operationis performed. For example, when a plurality of uplink component carriersare configured for a UE during one of the uplink subframes SF 7, SF 8,or SF9 (or during an uplink portion (e.g., a U-CUBS portion) of the Ssubframe 530 (e.g., SF 6)), and when a sum of the transmit powers of theuplink component carriers surpasses a total transmit power allowed forthe UE during a subframe, a power management operation may be performedto reduce the total transmit power of the uplink component carriers. Insome examples, one or more or all of the uplink component carriers maybe transmitted over a shared radio frequency spectrum band (e.g., aspart of the wireless communication 510 described with reference to FIG.5). In these examples, a power management operation may be performed onone of the uplink component carriers transmitted over the shared radiofrequency spectrum band. By way of example, FIG. 5 illustrates threescenarios (e.g., Scenario A, Scenario B, and Scenario C) in which apower management operation is performed on a first uplink componentcarrier transmitted over a shared radio frequency spectrum band as partof the wireless communication 510.

With reference to Scenario A, a minimum guaranteed power (e.g., Min., atransmit power greater than zero) may be configured for the first uplinkcomponent carrier in each of uplink subframes 7, 8, and 9 (SF 7, SF 8,and SF 9). When a power management operation needs to be performed forsubframe 7, the transmit power on the first uplink component carrier maybe reduced (or scaled) to a reduced power. However, because of theminimum guaranteed power, the transmit power may not be reduced belowthe minimum guaranteed power. In some examples, the power managementoperation performed for subframe 7 may only affect the transmit power onthe first uplink component carrier for subframe 7. In other examples,the power management operation preformed for subframe 7 may be carriedover to at least one (or each) subsequent subframe (or subsequent uplinksubframe) in the LBT radio frame 515. By way of example, Scenario Acarries over the power management operation performed for subframe 7 toeach of subframe 8 and subframe 9.

In a first variation of Scenario A, the power reduction on the firstuplink component carrier in subframe 7 may provide a reduced power thatremains above the minimum guaranteed power. In a second variation ofScenario A, a minimum guaranteed power may not be provided in one ormore of subframes 7, 8, or 9. In a third variation of Scenario A,different subframes may be subject to different power limitationconditions because of different requested transmit powers. As anexample, a first subframe may have a total requested power that is 3 dBover a maximum transmit power, while a second subframe may have a totalrequested power that is 5 dB over a maximum transmit power. In any ofthese variations, a power management operation may need to be performedon the first uplink component carrier for subframe 8 or subframe 9. Inthese examples, a further power reduction on the first uplink componentcarrier may be made in subframe 8 or subframe 9, with the reduced powerin the prior subframe serving as a maximum transmit power for thesubsequent subframe (e.g., the reduced power used in subframe 7 mayserve as a maximum transmit power for each of subframe 8 and subframe9).

The configuration of a minimum guaranteed power on an uplink componentcarrier may be useful in ensuring that a transmission over the sharedradio frequency spectrum band can be made. When a transmission over theshared radio frequency spectrum band cannot be made, the UE that wassupposed to make the transmission may need to perform another CCA (orextended CCA) to contend for access to the shared radio frequencyspectrum band, and it is possible that the UE may not win the CCA,therefore delaying the transmission and/or incurring costly overhead(e.g., increased power use, processing delays, etc.). The carryover of aresult of a power management operation, from a current subframe to asubsequent subframe, may be useful in that it helps to maintain thevalidity of a CCA determination made by another device (e.g., anotherUE, a base station, a wireless access point, a Wi-Fi station, etc.) inthe vicinity of the UE. For example, if a second UE successfullycontends for access to the shared radio frequency spectrum band while afirst UE is transmitting at a reduced power in a current subframe, butthe first UE then increases its transmit power for a subsequent subframewithout performing an updated CCA, the increased transmit power of thefirst UE in the subsequent subframe may interfere with a transmission ofthe second UE in the subsequent subframe.

With reference to Scenario B in FIG. 5, a power management operation maybe performed on the first uplink component carrier in subframe 7,resulting in a reduction of the transmit power on the first uplinkcomponent carrier to a reduced power. Then, because of the powerreduction in subframe 7, and because of the risk of further powerreductions in subsequent subframes, transmissions on the first uplinkcomponent carrier are dropped for all uplink subframes subsequent tosubframe 7 (e.g., transmissions on the first uplink component carrierare dropped for subframe 8 and subframe 9).

With reference to Scenario C in FIG. 5, a need for a power managementoperation on the first uplink component carrier may arise for subframe7, and because of the need for a power management operation, atransmission on the first uplink component carrier may be dropped. Atransmission on the first uplink component carrier may also be droppedfor at least one subsequent subframe (e.g., for each uplink subframebetween subframe 7 and the next frame boundary). Although Scenario Cresults in no transmissions being made on the first uplink componentcarrier, Scenario C ensures that a consistent power is maintained forthe duration of an uplink transmission (e.g., for each of subframe 7,subframe 8, and subframe 9).

Scenarios A, B, and C in FIG. 5 are exemplary, and other techniques forperforming a power management operation on an uplink component carriertransmitted over a shared radio frequency spectrum band are described inthe present disclosure.

FIG. 6 shows a block diagram 600 of an apparatus 615 for use in wirelesscommunication, in accordance with various aspects of the presentdisclosure. The apparatus 615 may be an example of aspects of one ormore of the UEs 115, 215, 215-a, 215-b, 215-c, 315, or 415 describedwith reference to FIG. 1, 2, 3, or 4. The apparatus 615 may also be orinclude a processor. The apparatus 615 may include a receiver component610, a wireless communication management component 620, or a transmittercomponent 630. Each of these components may be in communication witheach other.

The components of the apparatus 615 may, individually or collectively,be implemented using one or more application-specific integratedcircuits (ASICs) adapted to perform some or all of the applicablefunctions in hardware. Alternatively, the functions may be performed byone or more other processing units (or cores), on one or more integratedcircuits. In other examples, other types of integrated circuits may beused (e.g., Structured/Platform ASICs, Field Programmable Gate Arrays(FPGAs), and other Semi-Custom ICs), which may be programmed in anymanner known in the art. The functions of each component may also beimplemented, in whole or in part, with instructions embodied in amemory, formatted to be executed by one or more general orapplication-specific processors.

In some examples, the receiver component 610 may include at least oneradio frequency (RF) receiver, such as at least one RF receiver operableto receive transmissions over a licensed radio frequency spectrum band(e.g., a radio frequency spectrum band for which transmittingapparatuses may not contend for access because the radio frequencyspectrum band is licensed to specific users for specific uses, such as alicensed radio frequency spectrum band usable for LTE/LTE-Acommunications) or a shared radio frequency spectrum band (e.g., a radiofrequency spectrum band for which transmitting apparatuses may need tocontend for access because the radio frequency spectrum band isavailable for unlicensed use, such as Wi-Fi use). In some examples, thelicensed radio frequency spectrum band or the shared radio frequencyspectrum band may be used for LTE/LTE-A communications, as described,for example, with reference to FIG. 1, 2, 3, or 4. The receivercomponent 610 may be used to receive various types of data or controlsignals (i.e., transmissions) over one or more communication links of awireless communication system, such as one or more communication linksof the wireless communication system 100, 200, 300, or 400 describedwith reference to FIG. 1, 2, 3, or 4. The communication links may beestablished over the licensed radio frequency spectrum band or theshared radio frequency spectrum band.

In some examples, the transmitter component 630 may include at least oneRF transmitter, such as at least one RF transmitter operable to transmitover the licensed radio frequency spectrum band or the shared radiofrequency spectrum band. The transmitter component 630 may be used totransmit various types of data or control signals (i.e., transmissions)over one or more communication links of a wireless communication system,such as one or more communication links of the wireless communicationsystem 100, 200, 300, or 400 described with reference to FIG. 1, 2, 3,or 4. The communication links may be established over the licensed radiofrequency spectrum band or the shared radio frequency spectrum band.

In some examples, the wireless communication management component 620may be used to manage one or more aspects of wireless communication forthe apparatus 615. In some examples, the wireless communicationmanagement component 620 may include a component carrier managementcomponent 635 or a power management component 640.

In some examples, the component carrier management component 635 may beused to identify one or more of a plurality of component carriersconfigured for a UE (e.g., a UE including the apparatus 615). In someexamples, the plurality of component carriers may be configured for acarrier aggregation operation for the UE. In some examples, theplurality of component carriers may be configured for adual-connectivity operation for the UE. In some examples, the pluralityof component carriers may include a first uplink component carrier. Insome examples, the plurality of component carriers may also include asecond uplink component carrier.

The component carrier management component 635 may also be used todetermine the radio frequency spectrum band(s) over which one or more ofthe plurality of component carriers is transmitted. For example, thecomponent carrier management component 635 may be used to determine theradio frequency spectrum band(s) over which the first uplink componentcarrier and/or the second uplink component carrier are transmitted. Insome examples, the component carrier management component 635 maydetermine that the first uplink component carrier is transmitted overthe shared radio frequency spectrum band. In some examples, thecomponent carrier management component 635 may determine that the seconduplink component carrier is transmitted over the shared radio frequencyspectrum band or the licensed radio frequency spectrum band.

In some examples, the power management component 640 may be used toperform a power management operation on one or more of the plurality ofcomponent carriers identified by the component carrier managementcomponent 635. The power management operation may be performed for acurrent subframe, and may be performed because, for example, the powermanagement component 640 determines that the initial or default powersettings for the plurality of component carriers configured for a UEincluding the apparatus 715 exceed an allowed total maximum transmitpower for the UE.

In some examples, the power management component 640 may be used toperform a power management operation on a first uplink component carrierfor a current subframe. The power management operation may be based atleast in part on a determination, by the component carrier managementcomponent 635, that the first uplink component carrier is transmittedover the shared radio frequency spectrum band.

In some examples, the power management operation performed on the firstuplink component carrier, for the current subframe, may includemaintaining a transmit power on the first uplink component carrier at orabove a minimum guaranteed power; scaling the transmit power on thefirst uplink component carrier to a reduced power for the currentsubframe; using a transmit power on the first uplink component carrier,during a subframe preceding the current subframe, as a maximum transmitpower on the first uplink component carrier for the current subframe;and/or dropping a transmission on the first uplink component carrier forthe current subframe.

FIG. 7 shows a block diagram 700 of an apparatus 715 for use in wirelesscommunication, in accordance with various aspects of the presentdisclosure. The apparatus 715 may be an example of aspects of one ormore of the UEs 115, 215, 215-a, 215-b, 215-c, 315, or 415 describedwith reference to FIG. 1, 2, 3, or 4, or aspects of the apparatus 615described with reference to FIG. 6. The apparatus 715 may also be orinclude a processor. The apparatus 715 may include a receiver component710, a wireless communication management component 720, or a transmittercomponent 730. Each of these components may be in communication witheach other.

The components of the apparatus 715 may, individually or collectively,be implemented using one or more ASICs adapted to perform some or all ofthe applicable functions in hardware. Alternatively, the functions maybe performed by one or more other processing units (or cores), on one ormore integrated circuits. In other examples, other types of integratedcircuits may be used (e.g., Structured/Platform ASICs, FPGAs, and otherSemi-Custom ICs), which may be programmed in any manner known in theart. The functions of each component may also be implemented, in wholeor in part, with instructions embodied in a memory, formatted to beexecuted by one or more general or application-specific processors.

In some examples, the receiver component 710 may include at least one RFreceiver, such as at least one RF receiver operable to receivetransmissions over a licensed radio frequency spectrum band (e.g., aradio frequency spectrum band for which transmitting apparatuses may notcontend for access because the radio frequency spectrum band is licensedto specific users for specific uses, such as a licensed radio frequencyspectrum band usable for LTE/LTE-A communications) or a shared radiofrequency spectrum band (e.g., a radio frequency spectrum band for whichtransmitting apparatuses may need to contend for access because theradio frequency spectrum band is available for unlicensed use, such asWi-Fi use). In some examples, the licensed radio frequency spectrum bandor the shared radio frequency spectrum band may be used for LTE/LTE-Acommunications, as described, for example, with reference to FIG. 1, 2,3, or 4. The receiver component 710 may in some cases include separatereceivers for the licensed radio frequency spectrum band and the sharedradio frequency spectrum band. The separate receivers may, in someexamples, take the form of an LTE/LTE-A receiver component forcommunicating over the licensed radio frequency spectrum band (e.g.,LTE/LTE-A receiver component for licensed RF spectrum band 712), and anLTE/LTE-A receiver component for communicating over the shared radiofrequency spectrum band (e.g., LTE/LTE-A receiver component for sharedRF spectrum band 714). The receiver component 710, including theLTE/LTE-A receiver component for licensed RF spectrum band 712 or theLTE/LTE-A receiver component for shared RF spectrum band 714, may beused to receive various types of data or control signals (i.e.,transmissions) over one or more communication links of a wirelesscommunication system, such as one or more communication links of thewireless communication system 100, 200, 300, or 400 described withreference to FIG. 1, 2, 3, or 4. The communication links may beestablished over the licensed radio frequency spectrum band or theshared radio frequency spectrum band.

In some examples, the transmitter component 730 may include at least oneRF transmitter, such as at least one RF transmitter operable to transmitover the licensed radio frequency spectrum band or the shared radiofrequency spectrum band. The transmitter component 730 may in some casesinclude separate transmitters for the licensed radio frequency spectrumband and the shared radio frequency spectrum band. The separatetransmitters may, in some examples, take the form of an LTE/LTE-Atransmitter component for communicating over the licensed radiofrequency spectrum band (e.g., LTE/LTE-A transmitter component forlicensed RF spectrum band 732), and an LTE/LTE-A transmitter componentfor communicating over the shared radio frequency spectrum band (e.g.,LTE/LTE-A transmitter component for shared RF spectrum band 734). Thetransmitter component 730, including the LTE/LTE-A transmitter componentfor licensed RF spectrum band 732 or the LTE/LTE-A transmitter componentfor shared RF spectrum band 734, may be used to transmit various typesof data or control signals (i.e., transmissions) over one or morecommunication links of a wireless communication system, such as one ormore communication links of the wireless communication system 100, 200,300, or 400 described with reference to FIG. 1, 2, 3, or 4. Thecommunication links may be established over the licensed radio frequencyspectrum band or the shared radio frequency spectrum band.

In some examples, the wireless communication management component 720may be used to manage one or more aspects of wireless communication forthe apparatus 715. In some examples, the wireless communicationmanagement component 720 may include a component carrier managementcomponent 735 or a power management component 740.

In some examples, the component carrier management component 735 may beused to identify one or more of a plurality of component carriersconfigured for a UE (e.g., a UE including the apparatus 715). In someexamples, the plurality of component carriers may be configured for acarrier aggregation operation for the UE. In some examples, theplurality of component carriers may be configured for adual-connectivity operation for the UE. In some examples, the pluralityof component carriers may include a first uplink component carrier. Insome examples, the plurality of component carriers may also include asecond uplink component carrier.

The component carrier management component 735 may also be used todetermine the radio frequency spectrum band(s) over which one or more ofthe plurality of component carriers is transmitted. For example, thecomponent carrier management component 735 may be used to determine theradio frequency spectrum band(s) over which the first uplink componentcarrier and/or the second uplink component carrier are transmitted. Insome examples, the component carrier management component 735 maydetermine that the first uplink component carrier is transmitted overthe shared radio frequency spectrum band. In some examples, thecomponent carrier management component 735 may determine that the seconduplink component carrier is transmitted over the shared radio frequencyspectrum band or the licensed radio frequency spectrum band.

In some examples, the power management component 740 may be used toperform a power management operation on one or more of the plurality ofcomponent carriers identified by the component carrier managementcomponent 735. The power management operation may be performed for acurrent subframe, and may be performed because, for example, the powermanagement component 740 determines that the initial or default powersettings for the plurality of component carriers configured for a UEincluding the apparatus 715 exceed an allowed total maximum transmitpower for the UE. In some examples, the power management component 740may include a shared radio frequency spectrum band power managementcomponent 745, a licensed radio frequency spectrum band power managementcomponent 750, or an uplink scheduling management component 775.

In some examples, the shared radio frequency spectrum band powermanagement component 745 may be used to perform a power managementoperation on one or more component carriers based on a determination, bythe component carrier management component 735, that the one or morecomponent carriers are uplink component carriers transmitted over theshared radio frequency spectrum band. For example, the shared radiofrequency spectrum band power management component 745 may be used toperform a power management operation, for a current subframe, on a firstuplink component carrier identified by the component carrier managementcomponent 735. In some examples, the shared radio frequency spectrumband power management component 745 may include a minimum guaranteedpower management component 755, a power scaling component 760, athreshold power reduction determination component 765, or a powerconsistency management component 770. For purposes of illustration,exemplary uses and operations of the minimum guaranteed power managementcomponent 755, the power scaling component 760, the threshold powerreduction determination component 765, and the power consistencymanagement component 770 are described below in the context ofperforming a power management operation on a first uplink componentcarrier transmitted over the shared radio frequency spectrum band. Thesecomponents may also be used to perform a power management operation onone or more other uplink component carriers transmitted over the sharedradio frequency spectrum band.

In some examples, the minimum guaranteed power management component 755may be used to maintain, on the first uplink component carrier and forthe current subframe, a transmit power above a minimum guaranteed power.For example, the power scaling component 760 may be used to scale thetransmit power on the first uplink component carrier to a reduced power,and the minimum guaranteed power management component 755 may ensurethat the reduced power does not fall below the minimum guaranteed power.

In some examples, the minimum guaranteed power may depend on a channeltype or uplink information type transmitted on the first uplinkcomponent carrier. For example, the minimum guaranteed power may includeat least one of a PUCCH minimum guaranteed power component and a PUSCHguaranteed minimum power component, with the minimum guaranteed power atwhich the transmit power of the first uplink component carrier ismaintained depending on whether a PUCCH and/or a PUSCH is scheduled tobe transmitted on the first uplink component carrier during the currentsubframe. When a PUCCH is scheduled to be transmitted on the firstuplink component carrier during the current subframe, the minimumguaranteed power may include the PUCCH minimum guaranteed powercomponent. When a PUSCH is scheduled to be transmitted on the firstuplink component carrier during the current subframe, the minimumguaranteed power may include the PUSCH minimum guaranteed powercomponent. When a PUCCH and a PUSCH are scheduled to be transmitted onthe first uplink component carrier during the current subframe, theminimum guaranteed power may include a combination and/or scaledpercentage of the PUCCH minimum guaranteed power component and/or thePUSCH minimum guaranteed power component. In the case of scheduling botha PUCCH and a PUSCH on the first uplink component carrier during thecurrent subframe, the minimum guaranteed power may also include aseparately defined PUCCH/PUSCH minimum guaranteed power component. Asanother example, if a hybrid automatic repeat request (HARQ)acknowledgement (ACK) is present, a first minimum guaranteed power maybe used, and if a channel state information (CSI) report is present, asecond minimum guaranteed power may be used.

When a power management operation is performed by the shared radiofrequency spectrum band power management component 745 for one or moreother component carriers in the plurality of component carriers, andwhen the one or more other component carriers include at least a seconduplink component carrier, the same minimum guaranteed power or differentminimum guaranteed powers may be maintained for the first uplinkcomponent carrier and the second uplink component carrier.

In some examples, the power scaling component 760 may be used to scale atransmit power on the first uplink component carrier to a reduced powerfor the current subframe. The power scaling component 760 may also oralternatively be configured to drop a transmission on the first uplinkcomponent carrier for the current subframe. In some examples, thetransmission on the first uplink component carrier may be dropped forthe current subframe because of a need to perform a power managementoperation on the first uplink component carrier, or because of a need toscale the transmit power on the first uplink component carrier. In someexamples, the transmission on the first uplink component carrier may bedropped for the current subframe because a scaling of transmit power onthe first uplink component carrier surpasses a threshold power reduction(as determined, for example, by the threshold power reductiondetermination component 765).

In some examples, the threshold power reduction determination component765 may be used to determine whether a power management operationperformed by the shared radio frequency spectrum band power managementcomponent 745 results in power reduction that surpasses a thresholdpower reduction. A determination made by the threshold power reductiondetermination component 765 may be used, for example by the powerscaling component 760 or the power consistency management component 770to determine, for example, whether a transmission on the first uplinkcomponent carrier should be dropped. The determination made by thethreshold power reduction determination component 765 may also be usedby the uplink scheduling management component 775, to determine anscheduling for a subframe.

In some examples, the power consistency management component 770 may beused to manage the power level on the first uplink component carrierfrom subframe-to-subframe. For example, the power consistency managementcomponent 770 may use a reduced power on the first uplink componentcarrier, in a current subframe, as a maximum transmit power on the firstuplink component carrier for at least one subsequent subframe followingthe current subframe. Alternatively, the power consistency managementcomponent 770 may be used to drop a transmission on the first uplinkcomponent carrier for at least one subsequent subframe following thecurrent subframe. In some examples, the at least one subsequent subframefollowing the current subframe may include at least one uplink subframebetween the current subframe and a boundary of a subsequent frame. Insome examples, the at least one subsequent subframe following thecurrent subframe may include each of a number of uplink subframesbetween the current subframe and the boundary of the subsequent frame.

In some examples, the performance of a power management operation on thefirst uplink component carrier, by the power consistency managementcomponent 770, may be triggered by a need to perform a power managementoperation on the first uplink component carrier for a current subframe;or by a scaling of transmit power on the first uplink component carrierfor the current subframe; or by a scaling of transmit power on the firstuplink component carrier for the current subframe, which scalingsurpasses a threshold power reduction; or by a dropping of atransmission on the first uplink component carrier for the currentsubframe.

In some examples, and upon dropping a transmission on an uplinkcomponent carrier transmitted over the shared radio frequency spectrumband, the shared radio frequency spectrum band power managementcomponent 745 may trigger the performance of a CCA for at least onesubsequent uplink subframe following a subframe in which a transmissionhas been dropped. In some examples, the CCA may take the form of anextended CCA.

In some examples, the licensed radio frequency spectrum band powermanagement component 750 may be used to perform a power managementoperation on one or more component carriers based on a determination, bythe component carrier management component 735, that the one or morecomponent carriers are uplink component carriers transmitted over thelicensed radio frequency spectrum band.

In some examples, the uplink scheduling management component 775 may beused to determine which of a number of uplink schedulings is used for anuplink component carrier during a current subframe. By way of example,an exemplary operation of the uplink scheduling management component 775is described herein in the context of uplink scheduling for a firstuplink component carrier transmitted over the shared radio frequencyspectrum band.

In some examples, the uplink scheduling management component 775 mayreceive a first uplink scheduling for the first uplink component carrierfor a current subframe, and receive a second uplink scheduling for thefirst uplink component carrier for the current subframe. When a powermanagement operation is performed on the first uplink component carrierfor the current subframe, the uplink scheduling management component 775may use the second uplink scheduling for the first uplink componentcarrier for the current subframe. However, when a power managementoperation is not performed on the first uplink component carrier for thecurrent subframe, the uplink scheduling management component 775 may usethe first uplink scheduling for the first uplink component carrier forthe current subframe. Alternatively, the uplink scheduling managementcomponent 775 may use the first uplink scheduling or the second uplinkscheduling based at least in part on a condition of a power managementoperation performed. Alternatively, and upon the total transmit power onthe first uplink component carrier being scaled to a reduced power forthe current subframe, the uplink scheduling management component 775 mayuse the first uplink scheduling for the first uplink component carrierfor the current subframe when the scaling does not surpass a thresholdpower reduction, and use the second uplink scheduling for the firstuplink component carrier for the current subframe when the scalingsurpasses the threshold power reduction.

FIG. 8 shows a block diagram 800 of a UE 815 for use in wirelesscommunication, in accordance with various aspects of the presentdisclosure. The UE 815 may have various configurations and may beincluded or be part of a personal computer (e.g., a laptop computer, anetbook computer, a tablet computer, etc.), a cellular telephone, a PDA,a digital video recorder (DVR), an internet appliance, a gaming console,an e-reader, etc. The UE 815 may, in some examples, have an internalpower supply (not shown), such as a small battery, to facilitate mobileoperation. In some examples, the UE 815 may be an example of aspects ofone or more of the UE 115, 215, 215-a, 215-b, 215-c, 315, or 415described with reference to FIG. 1, 2, 3, or 4, or aspects of one ormore of the apparatuses 615 or 715 described with reference to FIG. 6 or7. The UE 815 may be configured to implement at least some of the UE orapparatus features and functions described with reference to FIG. 1, 2,3, 4, 5, 6, or 7.

The UE 815 may include a UE processor component 810, a UE memorycomponent 820, at least one UE transceiver component (represented by UEtransceiver component(s) 830), at least one UE antenna (represented byUE antenna(s) 840), or a UE wireless communication management component860. Each of these components may be in communication with each other,directly or indirectly, over one or more buses 835.

The UE memory component 820 may include random access memory (RAM) orread-only memory (ROM). The UE memory component 820 may storecomputer-readable, computer-executable code 825 containing instructionsthat are configured to, when executed, cause the UE processor component810 to perform various functions described herein related to wirelesscommunication, including the performance of a power management operationon one or more of a plurality of component carriers configured for theUE 815. Alternatively, the code 825 may not be directly executable bythe UE processor component 810 but be configured to cause the UE 815(e.g., when compiled and executed) to perform various of the functionsdescribed herein.

The UE processor component 810 may include an intelligent hardwaredevice, e.g., a central processing unit (CPU), a microcontroller, anASIC, etc. The UE processor component 810 may process informationreceived through the UE transceiver component(s) 830 or information tobe sent to the UE transceiver component(s) 830 for transmission throughthe UE antenna(s) 840. The UE processor component 810 may handle, aloneor in connection with the UE wireless communication management component860, various aspects of communicating over (or managing communicationsover) a licensed radio frequency spectrum band (e.g., a radio frequencyspectrum band for which apparatuses do not contend for access becausethe radio frequency spectrum band is licensed to specific users forspecific uses, such as a licensed radio frequency spectrum band usablefor LTE/LTE-A communications) or an shared radio frequency spectrum band(e.g., a radio frequency spectrum band for which apparatuses may need tocontend for access because the radio frequency spectrum band isavailable for unlicensed use, such as Wi-Fi use).

The UE transceiver component(s) 830 may include a modem configured tomodulate packets and provide the modulated packets to the UE antenna(s)840 for transmission, and to demodulate packets received from the UEantenna(s) 840. The UE transceiver component(s) 830 may, in someexamples, be implemented as one or more UE transmitter components andone or more separate UE receiver components. The UE transceivercomponent(s) 830 may support communications in the licensed radiofrequency spectrum band or the shared radio frequency spectrum band. TheUE transceiver component(s) 830 may be configured to communicatebi-directionally, via the UE antenna(s) 840, with one or more of thebase stations 105, 205, 205-a, 305, 405, or 405-a described withreference to FIG. 1, 2, 3, or 4. While the UE 815 may include a singleUE antenna, there may be examples in which the UE 815 may includemultiple UE antennas 840.

The UE state component 850 may be used, for example, to managetransitions of the UE 815 between an RRC idle state and an RRC connectedstate, and may be in communication with other components of the UE 815,directly or indirectly, over the one or more buses 835. The UE statecomponent 850, or portions of it, may include a processor, or some orall of the functions of the UE state component 850 may be performed bythe UE processor component 810 or in connection with the UE processorcomponent 810.

The UE wireless communication management component 860 may be configuredto perform or control some or all of the UE or apparatus features orfunctions described with reference to FIG. 1, 2, 3, 4, 5, 6, or 7related to wireless communication over a licensed radio frequencyspectrum band or a shared radio frequency spectrum band. For example,the UE wireless communication management component 860 may be configuredto support a supplemental downlink mode, a carrier aggregation mode, astandalone mode, or a dual-connectivity mode using the licensed radiofrequency spectrum band or the shared radio frequency spectrum band. TheUE wireless communication management component 860 may include a UELTE/LTE-A component for licensed RF spectrum band 865 configured tohandle LTE/LTE-A communications in the licensed radio frequency spectrumband, and a UE LTE/LTE-A component for shared RF spectrum band 870configured to handle LTE/LTE-A communications in the shared radiofrequency spectrum band. The UE wireless communication managementcomponent 860, or portions of it, may include a processor, or some orall of the functions of the UE wireless communication managementcomponent 860 may be performed by the UE processor component 810 or inconnection with the UE processor component 810. In some examples, the UEwireless communication management component 860 may be an example of thewireless communication management component 620 or 720 described withreference to FIG. 6 or 7.

FIG. 9 shows a block diagram 900 of a base station 905 (e.g., a basestation forming part or all of an eNB) for use in wirelesscommunication, in accordance with various aspects of the presentdisclosure. In some examples, the base station 905 may be an example ofone or more aspects of the base station 105, 205, 205-a, 305, 405, or405-a described with reference to FIG. 1, 2, 3, or 4. The base station905 may be configured to implement or facilitate at least some of thebase station features and functions described with reference to FIG. 1,2, 3, 4, or 5.

The base station 905 may include a base station processor component 910,a base station memory component 920, at least one base stationtransceiver component (represented by base station transceivercomponent(s) 950), at least one base station antenna (represented bybase station antenna(s) 955), or a base station wireless communicationmanagement component 960. The base station 905 may also include one ormore of a base station communications component 930 or a networkcommunications component 940. Each of these components may be incommunication with each other, directly or indirectly, over one or morebuses 935.

The base station memory component 920 may include RAM or ROM. The basestation memory component 920 may store computer-readable,computer-executable code 925 containing instructions that are configuredto, when executed, cause the base station processor component 910 toperform various functions described herein related to wirelesscommunication, including the transmission of alternative uplinkschedulings to a UE. Alternatively, the code 925 may not be directlyexecutable by the base station processor component 910 but be configuredto cause the base station 905 (e.g., when compiled and executed) toperform various of the functions described herein.

The base station processor component 910 may include an intelligenthardware device, e.g., a CPU, a microcontroller, an ASIC, etc. The basestation processor component 910 may process information received throughthe base station transceiver component(s) 950, the base stationcommunications component 930, or the network communications component940. The base station processor component 910 may also processinformation to be sent to the transceiver component(s) 950 fortransmission through the antenna(s) 955, to the base stationcommunications component 930, for transmission to one or more other basestations 905-a and 905-b, or to the network communications component 940for transmission to a core network 945, which may be an example of oneor more aspects of the core network 130 described with reference toFIG. 1. The base station processor component 910 may handle, alone or inconnection with the base station wireless communication managementcomponent 960, various aspects of communicating over (or managingcommunications over) a licensed radio frequency spectrum band (e.g., aradio frequency spectrum band for which apparatuses do not contend foraccess because the radio frequency spectrum band is licensed to specificusers for specific uses, such as a licensed radio frequency spectrumband usable for LTE/LTE-A communications) or an shared radio frequencyspectrum band (e.g., a radio frequency spectrum band for whichapparatuses may need to contend for access because the radio frequencyspectrum band is available for unlicensed use, such as Wi-Fi use).

The base station transceiver component(s) 950 may include a modemconfigured to modulate packets and provide the modulated packets to thebase station antenna(s) 955 for transmission, and to demodulate packetsreceived from the base station antenna(s) 955. The base stationtransceiver component(s) 950 may, in some examples, be implemented asone or more base station transmitter components and one or more separatebase station receiver components. The base station transceivercomponent(s) 950 may support communications in the licensed radiofrequency spectrum band or the shared radio frequency spectrum band. Thebase station transceiver component(s) 950 may be configured tocommunicate bi-directionally, via the antenna(s) 955, with one or moreUEs or apparatuses, such as one or more of the UEs 115, 215, 215-a,215-b, 215-c, 315, 415, or 815 described with reference to FIG. 1, 2, 3,4, or 8, or one or more of the apparatuses 615 or 715 described withreference to FIG. 16 or 17. The base station 905 may, for example,include multiple base station antennas 955 (e.g., an antenna array). Thebase station 905 may communicate with the core network 945 through thenetwork communications component 940. The base station 905 may alsocommunicate with other base stations, such as the base stations 905-aand 905-b, using the base station communications component 930.

The base station wireless communication management component 960 may beconfigured to perform or control some or all of the features orfunctions described with reference to FIG. 1, 2, 3, 4, or 5 related towireless communication over a licensed radio frequency spectrum band ora shared radio frequency spectrum band. For example, the base stationwireless communication management component 960 may be configured tosupport a supplemental downlink mode, a carrier aggregation mode, astandalone mode using, or a dual-connectivity mode using the licensedradio frequency spectrum band or the shared radio frequency spectrumband. The base station wireless communication management component 960may include a base station LTE/LTE-A component for licensed RF spectrumband 965 configured to handle LTE/LTE-A communications in the licensedradio frequency spectrum band, and a base station LTE/LTE-A componentfor shared RF spectrum band 970 configured to handle LTE/LTE-Acommunications in the shared radio frequency spectrum band. The basestation wireless communication management component 960, or portions ofit, may include a processor, or some or all of the functions of the basestation wireless communication management component 960 may be performedby the base station processor component 910 or in connection with thebase station processor component 910.

FIG. 10 is a block diagram of a multiple input/multiple output (MIMO)communication system 1000 including a base station 1005 and a UE 1015,in accordance with various aspects of the present disclosure. The MIMOcommunication system 1000 may illustrate aspects of the wirelesscommunication system 100, 200, 300, or 400 described with reference toFIG. 1, 2, 3, or 4. The base station 1005 may be an example of aspectsof the base station 105, 205, 205-a, 305, 405, 405-a, or 905 describedwith reference to FIG. 1, 2, 3, 4, or 9. The base station 1005 may beequipped with antennas 1034 through 1035, and the UE 1015 may beequipped with antennas 1052 through 1053. In the MIMO communicationsystem 1000, the base station 1005 may be able to send data overmultiple communication links at the same time. Each communication linkmay be called a “layer” and the “rank” of the communication link mayindicate the number of layers used for communication. For example, in a2×2 MIMO communications system where base station 1005 transmits two“layers,” the rank of the communication link between the base station1005 and the UE 1015 is two.

At the base station 1005, a transmit processor 1020 may receive datafrom a data source. The transmit processor 1020 may process the data.The transmit processor 1020 may also generate control symbols orreference symbols. A transmit (Tx) MIMO processor 1030 may performspatial processing (e.g., precoding) on data symbols, control symbols,or reference symbols, if applicable, and may provide output symbolstreams to the transmit modulators 1032 through 1033. Each modulator1032 through 1033 may process a respective output symbol stream (e.g.,for OFDM, etc.) to obtain an output sample stream. Each modulator 1032through 1033 may further process (e.g., convert to analog, amplify,filter, and upconvert) the output sample stream to obtain a DL signal.In one example, DL signals from modulators 1032 through 1033 may betransmitted via the antennas 1034 through 1035, respectively.

The UE 1015 may be an example of aspects of the UE 115, 215, 215-a,215-b, 215-c, 315, 415, or 815 described with reference to FIG. 1, 2, 3,4, or 8, or aspects of the apparatus 615 or 715 described with referenceto FIG. 6 or 7. At the UE 1015, the UE antennas 1052 through 1053 mayreceive the DL signals from the base station 1005 and may provide thereceived signals to the demodulators 1054 through 1055, respectively.Each demodulator 1054 through 1055 may condition (e.g., filter, amplify,downconvert, and digitize) a respective received signal to obtain inputsamples. Each demodulator 1054 through 1055 may further process theinput samples (e.g., for OFDM, etc.) to obtain received symbols. A MIMOdetector 1056 may obtain received symbols from all the demodulators 1054through 1055, perform MIMO detection on the received symbols, ifapplicable, and provide detected symbols. A receive (Rx) processor 1058may process (e.g., demodulate, deinterleave, and decode) the detectedsymbols, providing decoded data for the UE 1015 to a data output, andprovide decoded control information to a processor 1080, or memory 1082.

The processor 1080 may in some cases execute stored instructions toinstantiate a wireless communication management component 1084. Thewireless communication management component 1084 may be an example ofaspects of the wireless communication management component 620, 720, or860 described with reference to FIG. 6, 7, or 8.

On the uplink (UL), at the UE 1015, a transmit processor 1064 mayreceive and process data from a data source. The transmit processor 1064may also generate reference symbols for a reference signal. The symbolsfrom the transmit processor 1064 may be precoded by a transmit MIMOprocessor 1066 if applicable, further processed by the modulators 1054through 1055 (e.g., for SC-FDMA, etc.), and be transmitted to the basestation 1005 in accordance with the transmission parameters receivedfrom the base station 1005. At the base station 1005, the UL signalsfrom the UE 1015 may be received by the antennas 1034 through 1035,processed by the demodulators 1032 through 1033, detected by a MIMOdetector 1036 if applicable, and further processed by a receiveprocessor 1038. The receive processor 1038 may provide decoded data to adata output and to the processor 1040 or memory 1042.

The processor 1040 may in some cases execute stored instructions toinstantiate a wireless communication management component 1086. Thewireless communication management component 1086 may be an example ofaspects of the wireless communication management component 960 describedwith reference to FIG. 9.

The components of the UE 1015 may, individually or collectively, beimplemented with one or more ASICs adapted to perform some or all of theapplicable functions in hardware. Each of the noted components may be ameans for performing one or more functions related to operation of theMIMO communication system 1000. Similarly, the components of the basestation 1005 may, individually or collectively, be implemented with oneor more ASICs adapted to perform some or all of the applicable functionsin hardware. Each of the noted components may be a means for performingone or more functions related to operation of the MIMO communicationsystem 1000.

FIG. 11 is a flow chart illustrating an example of a method 1100 forwireless communication, in accordance with various aspects of thepresent disclosure. For clarity, the method 1100 is described below withreference to aspects of one or more of the UEs 115, 215, 215-a, 215-b,215-c, 315, 415, 815, or 1015 described with reference to FIG. 1, 2, 3,4, 8, or 10, or aspects of one or more of the apparatuses 615 or 715described with reference to FIG. 6 or 17. In some examples, a UE orapparatus may execute one or more sets of codes to control thefunctional elements of the UE or apparatus to perform the functionsdescribed below. Additionally or alternatively, the UE or apparatus mayperform one or more of the functions described below usingspecial-purpose hardware. The method 1100 presumes that a determinationhas been made to perform a power management operation for a currentsubframe (e.g., because the initial or default power settings for aplurality of component carriers configured for a UE or apparatus, forthe current subframe, exceed an allowed total maximum transmit power forthe UE or apparatus).

At block 1105, the method 1100 may include identifying a first uplinkcomponent carrier of a plurality of component carriers configured for aUE. In some examples, the plurality of component carriers may beconfigured for a carrier aggregation operation for the UE. In someexamples, the plurality of component carriers may be configured for adual-connectivity operation for the UE. In some examples, one or moreadditional component carriers of the plurality of component carriers mayalso be identified at block 1105. In some examples, the one or moreadditional component carriers may include at least a second uplinkcomponent carrier. The operation(s) at block 1105 may be performed usingthe wireless communication management component 620, 720, 860, or 1084described with reference to FIG. 6, 7, 8, or 10, or the componentcarrier management component 635 or 735 described with reference to FIG.6 or 7.

At block 1110, the method 1100 may include determining that the firstuplink component carrier is transmitted over a shared radio frequencyspectrum band. The shared radio frequency spectrum band may include aradio frequency spectrum band for which transmitting apparatuses mayneed to contend for access because the radio frequency spectrum band isavailable for unlicensed use, such as Wi-Fi use. In some examples, theradio frequency spectrum band over which one or more other componentcarriers are carried may also be determined at block 1110. For example,it may be determined that the second uplink component carrier istransmitted over the shared radio frequency spectrum band, or that thesecond uplink component carrier is transmitted over a licensed radiofrequency spectrum band. The licensed radio frequency spectrum band mayinclude a radio frequency spectrum band for which transmittingapparatuses may not contend for access because the radio frequencyspectrum band is licensed to specific users for specific uses, such as alicensed radio frequency spectrum band usable for LTE/LTE-Acommunications. The operation(s) at block 1110 may be performed usingthe wireless communication management component 620, 720, 860, or 1084described with reference to FIG. 6, 7, 8, or 10, or the componentcarrier management component 635 or 735 described with reference to FIG.6 or 7.

At block 1115, the method 1100 may include performing a power managementoperation on the first uplink component carrier, for a current subframe,based at least in part on the determining performed at block 1110. Insome examples, a power management operation may also be performed atblock 1115 for one or more other component carriers in the plurality ofcomponent carriers. The operation(s) at block 1115 may be performedusing the wireless communication management component 620, 720, 860, or1084 described with reference to FIG. 6, 7, 8, or 10, the powermanagement component 640 or 740 described with reference to FIG. 6 or 7,or the shared radio frequency spectrum band power management component745 and/or licensed radio frequency spectrum band power managementcomponent 750 described with reference to FIG. 7.

In some examples, the power management operation performed at block 1115may include maintaining a transmit power on the first uplink componentcarrier at or above a minimum guaranteed power; scaling the transmitpower on the first uplink component carrier to a reduced power for thecurrent subframe; using a transmit power on the first uplink componentcarrier, during a subframe preceding the current subframe, as a maximumtransmit power on the first uplink component carrier for the currentsubframe; and/or dropping a transmission on the first uplink componentcarrier for the current subframe.

Thus, the method 1100 may provide for wireless communication. It shouldbe noted that the method 1100 is just one implementation and that theoperations of the method 1100 may be rearranged or otherwise modifiedsuch that other implementations are possible.

FIG. 12 is a flow chart illustrating an example of a method 1200 forwireless communication, in accordance with various aspects of thepresent disclosure. For clarity, the method 1200 is described below withreference to aspects of one or more of the UEs 115, 215, 215-a, 215-b,215-c, 315, 415, 815, or 1015 described with reference to FIG. 1, 2, 3,4, 8, or 10, or aspects of one or more of the apparatuses 615 or 715described with reference to FIG. 6 or 17. In some examples, a UE orapparatus may execute one or more sets of codes to control thefunctional elements of the UE or apparatus to perform the functionsdescribed below. Additionally or alternatively, the UE or apparatus mayperform one or more of the functions described below usingspecial-purpose hardware. The method 1200 presumes that a determinationhas been made to perform a power management operation for a currentsubframe (e.g., because the initial or default power settings for aplurality of component carriers configured for a UE or apparatus, forthe current subframe, exceed an allowed total maximum transmit power forthe UE or apparatus).

At block 1205, the method 1200 may include identifying a first uplinkcomponent carrier of a plurality of component carriers configured for aUE. In some examples, the plurality of component carriers may beconfigured for a carrier aggregation operation for the UE. In someexamples, the plurality of component carriers may be configured for adual-connectivity operation for the UE. In some examples, one or moreadditional component carriers of the plurality of component carriers mayalso be identified at block 1205. In some examples, the one or moreadditional component carriers may include at least a second uplinkcomponent carrier. The operation(s) at block 1205 may be performed usingthe wireless communication management component 620, 720, 860, or 1084described with reference to FIG. 6, 7, 8, or 10, or the componentcarrier management component 635 or 735 described with reference to FIG.6 or 7.

At block 1210, the method 1200 may include determining that the firstuplink component carrier is transmitted over a shared radio frequencyspectrum band. The shared radio frequency spectrum band may include aradio frequency spectrum band for which transmitting apparatuses mayneed to contend for access because the radio frequency spectrum band isavailable for unlicensed use, such as Wi-Fi use. In some examples, theradio frequency spectrum band over which one or more other componentcarriers are carried may also be determined at block 1210. For example,it may be determined that the second uplink component carrier istransmitted over the shared radio frequency spectrum band, or that thesecond uplink component carrier is transmitted over a licensed radiofrequency spectrum band. The licensed radio frequency spectrum band mayinclude a radio frequency spectrum band for which transmittingapparatuses may not contend for access because the radio frequencyspectrum band is licensed to specific users for specific uses, such as alicensed radio frequency spectrum band usable for LTE/LTE-Acommunications. The operation(s) at block 1210 may be performed usingthe wireless communication management component 620, 720, 860, or 1084described with reference to FIG. 6, 7, 8, or 10, or the componentcarrier management component 635 or 735 described with reference to FIG.6 or 7.

At block 1215, the method 1200 may include performing a power managementoperation on the first uplink component carrier, for a current subframe,based at least in part on the determining performed at block 1210.Performing the power management operation on the first uplink componentcarrier may include maintaining, on the first uplink component carrierand for the current subframe, a transmit power above a minimumguaranteed power. In some examples, performing the power managementoperation on the first uplink component carrier may include scaling thetransmit power on the first uplink component carrier to a reduced power,but not below the minimum guaranteed power. In some examples, a powermanagement operation may also be performed at block 1215 for one or moreother component carriers in the plurality of component carriers. Theoperation(s) at block 1215 may be performed using the wirelesscommunication management component 620, 720, 860, or 1084 described withreference to FIG. 6, 7, 8, or 10, the power management component 640 or740 described with reference to FIG. 6 or 7, or the shared radiofrequency spectrum band power management component 745, licensed radiofrequency spectrum band power management component 750, and/or minimumguaranteed power management component 755 described with reference toFIG. 7.

In some examples, the minimum guaranteed power may be dependent on achannel type or uplink information type transmitted on the first uplinkcomponent carrier. For example, the minimum guaranteed power may includeat least one of a PUCCH minimum guaranteed power component and a PUSCHguaranteed minimum power component, with the minimum guaranteed power atwhich the transmit power of the first uplink component carrier ismaintained depending on whether a PUCCH and/or a PUSCH is scheduled tobe transmitted on the first uplink component carrier during the currentsubframe. When a PUCCH is scheduled to be transmitted on the firstuplink component carrier during the current subframe, the minimumguaranteed power may include the PUCCH minimum guaranteed powercomponent. When a PUSCH is scheduled to be transmitted on the firstuplink component carrier during the current subframe, the minimumguaranteed power may include the PUSCH minimum guaranteed powercomponent. When a PUCCH and a PUSCH are scheduled to be transmitted onthe first uplink component carrier during the current subframe, theminimum guaranteed power may include a combination and/or scaledpercentage of the PUCCH minimum guaranteed power component and/or thePUSCH minimum guaranteed power component. In the case of scheduling botha PUCCH and a PUSCH on the first uplink component carrier during thecurrent subframe, the minimum guaranteed power may also include aseparately defined PUCCH/PUSCH minimum guaranteed power component.

When a power management operation is performed at block 1215 for one ormore other component carriers in the plurality of component carriers,and when the one or more other component carriers include at least thesecond uplink component carrier, the same minimum guaranteed power ordifferent minimum guaranteed powers may be maintained for the firstuplink component carrier and the second uplink component carrier.

Thus, the method 1200 may provide for wireless communication. It shouldbe noted that the method 1200 is just one implementation and that theoperations of the method 1200 may be rearranged or otherwise modifiedsuch that other implementations are possible.

FIG. 13 is a flow chart illustrating an example of a method 1300 forwireless communication, in accordance with various aspects of thepresent disclosure. For clarity, the method 1300 is described below withreference to aspects of one or more of the UEs 115, 215, 215-a, 215-b,215-c, 315, 415, 815, or 1015 described with reference to FIG. 1, 2, 3,4, 8, or 10, or aspects of one or more of the apparatuses 615 or 715described with reference to FIG. 6 or 17. In some examples, a UE orapparatus may execute one or more sets of codes to control thefunctional elements of the UE or apparatus to perform the functionsdescribed below. Additionally or alternatively, the UE or apparatus mayperform one or more of the functions described below usingspecial-purpose hardware. The method 1300 presumes that a determinationhas been made to perform a power management operation for a currentsubframe (e.g., because the initial or default power settings for aplurality of component carriers configured for a UE or apparatus, forthe current subframe, exceed an allowed total maximum transmit power forthe UE or apparatus).

At block 1305, the method 1300 may include identifying a first uplinkcomponent carrier of a plurality of component carriers configured for aUE. In some examples, the plurality of component carriers may beconfigured for a carrier aggregation operation for the UE. In someexamples, the plurality of component carriers may be configured for adual-connectivity operation for the UE. In some examples, one or moreadditional component carriers of the plurality of component carriers mayalso be identified at block 1305. In some examples, the one or moreadditional component carriers may include at least a second uplinkcomponent carrier. The operation(s) at block 1305 may be performed usingthe wireless communication management component 620, 720, 860, or 1084described with reference to FIG. 6, 7, 8, or 10, or the componentcarrier management component 635 or 735 described with reference to FIG.6 or 7.

At block 1310, the method 1300 may include determining that the firstuplink component carrier is transmitted over a shared radio frequencyspectrum band. The shared radio frequency spectrum band may include aradio frequency spectrum band for which transmitting apparatuses mayneed to contend for access because the radio frequency spectrum band isavailable for unlicensed use, such as Wi-Fi use. In some examples, theradio frequency spectrum band over which one or more other componentcarriers are carried may also be determined at block 1310. For example,it may be determined that the second uplink component carrier istransmitted over the shared radio frequency spectrum band, or that thesecond uplink component carrier is transmitted over a licensed radiofrequency spectrum band. The licensed radio frequency spectrum band mayinclude a radio frequency spectrum band for which transmittingapparatuses may not contend for access because the radio frequencyspectrum band is licensed to specific users for specific uses, such as alicensed radio frequency spectrum band usable for LTE/LTE-Acommunications. The operation(s) at block 1310 may be performed usingthe wireless communication management component 620, 720, 860, or 1084described with reference to FIG. 6, 7, 8, or 10, or the componentcarrier management component 635 or 735 described with reference to FIG.6 or 7.

At block 1315, the method 1300 may include performing a power managementoperation on the first uplink component carrier, for a current subframe,based at least in part on the determining performed at block 1310.Performing the power management operation on the first uplink componentcarrier may include dropping a transmission on the first uplinkcomponent carrier for the current subframe. In some examples, a powermanagement operation may also be performed at block 1315 for one or moreother component carriers in the plurality of component carriers. Theoperation(s) at block 1315 may be performed using the wirelesscommunication management component 620, 720, 860, or 1084 described withreference to FIG. 6, 7, 8, or 10, the power management component 640 or740 described with reference to FIG. 6 or 7, or the shared radiofrequency spectrum band power management component 745, licensed radiofrequency spectrum band power management component 750, and/or powerscaling component 760 described with reference to FIG. 7.

At block 1320, the method 1300 may include dropping a transmission onthe first uplink component carrier for at least one subsequent subframefollowing the current subframe. In some examples, the at least onesubsequent subframe following the current subframe may include at leastone uplink subframe between the current subframe and a boundary of asubsequent frame. In some examples, the at least one subsequent subframefollowing the current subframe may include each of a number of uplinksubframes between the current subframe and the boundary of thesubsequent frame. The operation(s) at block 1320 may be performed usingthe wireless communication management component 620, 720, 860, or 1084described with reference to FIG. 6, 7, 8, or 10, the power managementcomponent 640 or 740 described with reference to FIG. 6 or 7, or theshared radio frequency spectrum band power management component 745and/or power consistency management component 770 described withreference to FIG. 7.

At block 1325, the method 1300 may include performing a CCA for theshared radio frequency spectrum band. The CCA may be performed for atleast one subsequent uplink subframe following the current subframe. Insome examples, the CCA may take the form of an extended CCA. In someexamples, the operation(s) at block 1325 may follow the operation(s) atblock 1320. The operation(s) at block 1325 may be performed using thewireless communication management component 620, 720, 860, or 1084described with reference to FIG. 6, 7, 8, or 10, the power managementcomponent 640 or 740 described with reference to FIG. 6 or 7, or theshared radio frequency spectrum band power management component 745and/or power consistency management component 770 described withreference to FIG. 7.

Thus, the method 1300 may provide for wireless communication. It shouldbe noted that the method 1300 is just one implementation and that theoperations of the method 1300 may be rearranged or otherwise modifiedsuch that other implementations are possible.

FIG. 14 is a flow chart illustrating an example of a method 1400 forwireless communication, in accordance with various aspects of thepresent disclosure. For clarity, the method 1400 is described below withreference to aspects of one or more of the UEs 115, 215, 215-a, 215-b,215-c, 315, 415, 815, or 1015 described with reference to FIG. 1, 2, 3,4, 8, or 10, or aspects of one or more of the apparatuses 615 or 715described with reference to FIG. 6 or 17. In some examples, a UE orapparatus may execute one or more sets of codes to control thefunctional elements of the UE or apparatus to perform the functionsdescribed below. Additionally or alternatively, the UE or apparatus mayperform one or more of the functions described below usingspecial-purpose hardware. The method 1400 presumes that a determinationhas been made to perform a power management operation for a currentsubframe (e.g., because the initial or default power settings for aplurality of component carriers configured for a UE or apparatus, forthe current subframe, exceed an allowed total maximum transmit power forthe UE or apparatus).

At block 1405, the method 1400 may include identifying a first uplinkcomponent carrier of a plurality of component carriers configured for aUE. In some examples, the plurality of component carriers may beconfigured for a carrier aggregation operation for the UE. In someexamples, the plurality of component carriers may be configured for adual-connectivity operation for the UE. In some examples, one or moreadditional component carriers of the plurality of component carriers mayalso be identified at block 1405. In some examples, the one or moreadditional component carriers may include at least a second uplinkcomponent carrier. The operation(s) at block 1405 may be performed usingthe wireless communication management component 620, 720, 860, or 1084described with reference to FIG. 6, 7, 8, or 10, or the componentcarrier management component 635 or 735 described with reference to FIG.6 or 7.

At block 1410, the method 1400 may include determining that the firstuplink component carrier is transmitted over a shared radio frequencyspectrum band. The shared radio frequency spectrum band may include aradio frequency spectrum band for which transmitting apparatuses mayneed to contend for access because the radio frequency spectrum band isavailable for unlicensed use, such as Wi-Fi use. In some examples, theradio frequency spectrum band over which one or more other componentcarriers are carried may also be determined at block 1410. For example,it may be determined that the second uplink component carrier istransmitted over the shared radio frequency spectrum band, or that thesecond uplink component carrier is transmitted over a licensed radiofrequency spectrum band. The licensed radio frequency spectrum band mayinclude a radio frequency spectrum band for which transmittingapparatuses may not contend for access because the radio frequencyspectrum band is licensed to specific users for specific uses, such as alicensed radio frequency spectrum band usable for LTE/LTE-Acommunications. The operation(s) at block 1410 may be performed usingthe wireless communication management component 620, 720, 860, or 1084described with reference to FIG. 6, 7, 8, or 10, or the componentcarrier management component 635 or 735 described with reference to FIG.6 or 7.

At block 1415, the method 1400 may include performing a power managementoperation on the first uplink component carrier, for a current subframe,based at least in part on the determining performed at block 1410.Performing the power management operation on the first uplink componentcarrier may include scaling a transmit power on the first uplinkcomponent carrier to a reduced power for the current subframe. In someexamples, a power management operation may also be performed at block1415 for one or more other component carriers in the plurality ofcomponent carriers. The operation(s) at block 1415 may be performedusing the wireless communication management component 620, 720, 860, or1084 described with reference to FIG. 6, 7, 8, or 10, the powermanagement component 640 or 740 described with reference to FIG. 6 or 7,or the shared radio frequency spectrum band power management component745, licensed radio frequency spectrum band power management component750, and/or power scaling component 760 described with reference to FIG.7.

Following block 1415, the method 1400 may continue at block 1420, block1425, block 1430, or block 1435.

At block 1420, the method 1400 may include using the reduced power as amaximum transmit power on the first uplink component carrier for atleast one subsequent subframe following the current subframe. In someexamples, the at least one subsequent subframe following the currentsubframe may include at least one uplink subframe between the currentsubframe and a boundary of a subsequent frame. In some examples, the atleast one subsequent subframe following the current subframe may includeeach of a number of uplink subframes between the current subframe andthe boundary of the subsequent frame. The operation(s) at block 1420 maybe performed using the wireless communication management component 620,720, 860, or 1084 described with reference to FIG. 6, 7, 8, or 10, thepower management component 640 or 740 described with reference to FIG. 6or 7, or the shared radio frequency spectrum band power managementcomponent 745 and/or power consistency management component 770described with reference to FIG. 7.

At block 1425, the method 1400 may include dropping a transmission onthe first uplink component carrier for the current subframe. In someexamples, the operation(s) at block 1425 may be performed because a needto perform a power management operation exits (or because a need toscale the transmit power on the first uplink component carrier exists).In some examples, the operation(s) at block 1425 may be performedbecause it is determined at block 1430 that the scaling performed atblock 1415 surpasses a threshold power reduction.

The operation(s) at block 1425 may be performed using the wirelesscommunication management component 620, 720, 860, or 1084 described withreference to FIG. 6, 7, 8, or 10, the power management component 640 or740 described with reference to FIG. 6 or 7, or the shared radiofrequency spectrum band power management component 745, and/or powerconsistency management component 770 described with reference to FIG. 7.The operation(s) at block 1430 may be performed using the wirelesscommunication management component 620, 720, 860, or 1084 described withreference to FIG. 6, 7, 8, or 10, the power management component 640 or740 described with reference to FIG. 6 or 7, or the shared radiofrequency spectrum band power management component 745 and/or thresholdpower reduction determination component 765 described with reference toFIG. 7.

At block 1435, the method 1400 may include dropping a transmission onthe first uplink component carrier for at least one subsequent subframefollowing the current subframe. In some examples, the at least onesubsequent subframe following the current subframe may include at leastone uplink subframe between the current subframe and a boundary of asubsequent frame. In some examples, the at least one subsequent subframefollowing the current subframe may include each of a number of uplinksubframes between the current subframe and the boundary of thesubsequent frame.

In some examples, the operation(s) at block 1435 may be performedbecause the transmit power on the first uplink component carrier isscaled at block 1415. In some examples, the operation(s) at block 1435may be performed because a transmission on the first uplink componentcarrier is dropped for the current subframe at block 1425. In someexamples, the operation(s) at block 1435 may be performed because it isdetermined at block 1430 that the scaling performed at block 1415surpasses a threshold power reduction.

The operation(s) at block 1435 may be performed using the wirelesscommunication management component 620, 720, 860, or 1084 described withreference to FIG. 6, 7, 8, or 10, the power management component 640 or740 described with reference to FIG. 6 or 7, or the shared radiofrequency spectrum band power management component 745 and/or powerconsistency management component 770 described with reference to FIG. 7.

Thus, the method 1400 may provide for wireless communication. It shouldbe noted that the method 1400 is just one implementation and that theoperations of the method 1400 may be rearranged or otherwise modifiedsuch that other implementations are possible.

FIG. 15 is a flow chart illustrating an example of a method 1500 forwireless communication, in accordance with various aspects of thepresent disclosure. For clarity, the method 1500 is described below withreference to aspects of one or more of the UEs 115, 215, 215-a, 215-b,215-c, 315, 415, 815, or 1015 described with reference to FIG. 1, 2, 3,4, 8, or 10, or aspects of one or more of the apparatuses 615 or 715described with reference to FIG. 6 or 17. In some examples, a UE orapparatus may execute one or more sets of codes to control thefunctional elements of the UE or apparatus to perform the functionsdescribed below. Additionally or alternatively, the UE or apparatus mayperform one or more of the functions described below usingspecial-purpose hardware. The method 1500 presumes that a determinationhas been made to perform a power management operation for a currentsubframe (e.g., because the initial or default power settings for aplurality of component carriers configured for a UE or apparatus, forthe current subframe, exceed an allowed total maximum transmit power forthe UE or apparatus).

At block 1505, the method 1500 may include identifying a first uplinkcomponent carrier of a plurality of component carriers configured for aUE. In some examples, the plurality of component carriers may beconfigured for a carrier aggregation operation for the UE. In someexamples, the plurality of component carriers may be configured for adual-connectivity operation for the UE. In some examples, one or moreadditional component carriers of the plurality of component carriers mayalso be identified at block 1505. In some examples, the one or moreadditional component carriers may include at least a second uplinkcomponent carrier. The operation(s) at block 1505 may be performed usingthe wireless communication management component 620, 720, 860, or 1084described with reference to FIG. 6, 7, 8, or 10, or the componentcarrier management component 635 or 735 described with reference to FIG.6 or 7.

At block 1510, the method 1500 may include receiving a first uplinkscheduling for the first uplink component carrier for the currentsubframe, and receiving a second uplink scheduling for the first uplinkcomponent carrier for the current subframe. The operation(s) at block1510 may be performed using the wireless communication managementcomponent 620, 720, 860, or 1084 described with reference to FIG. 6, 7,8, or 10, or the uplink scheduling management component 775 describedwith reference to FIG. 7.

At block 1515, the method 1500 may include determining that the firstuplink component carrier is transmitted over a shared radio frequencyspectrum band. The shared radio frequency spectrum band may include aradio frequency spectrum band for which transmitting apparatuses mayneed to contend for access because the radio frequency spectrum band isavailable for unlicensed use, such as Wi-Fi use. In some examples, theradio frequency spectrum band over which one or more other componentcarriers are carried may also be determined at block 1515. For example,it may be determined that the second uplink component carrier istransmitted over the shared radio frequency spectrum band, or that thesecond uplink component carrier is transmitted over a licensed radiofrequency spectrum band. The licensed radio frequency spectrum band mayinclude a radio frequency spectrum band for which transmittingapparatuses may not contend for access because the radio frequencyspectrum band is licensed to specific users for specific uses, such as alicensed radio frequency spectrum band usable for LTE/LTE-Acommunications. The operation(s) at block 1515 may be performed usingthe wireless communication management component 620, 720, 860, or 1084described with reference to FIG. 6, 7, 8, or 10, or the componentcarrier management component 635 or 735 described with reference to FIG.6 or 7.

At block 1520, the method 1500 may include performing a power managementoperation on the first uplink component carrier, for a current subframe,based at least in part on the determining performed at block 1515. Insome examples, a power management operation may also be performed atblock 1520 for one or more other component carriers in the plurality ofcomponent carriers. The operation(s) at block 1520 may be performedusing the wireless communication management component 620, 720, 860, or1084 described with reference to FIG. 6, 7, 8, or 10, the powermanagement component 640 or 740 described with reference to FIG. 6 or 7,or the shared radio frequency spectrum band power management component745 and/or licensed radio frequency spectrum band power managementcomponent 750 described with reference to FIG. 7.

Following block 1520, the method 1500 may continue at block 1525, block1530, or block 1535.

At block 1525, the method 1500 may include using the second uplinkscheduling, based at least in part on performing the power managementoperation. When the power management operation is not performed, thefirst uplink scheduling may be used. The operation(s) at block 1525 maybe performed using the wireless communication management component 620,720, 860, or 1084 described with reference to FIG. 6, 7, 8, or 10, orthe uplink scheduling management component 775 described with referenceto FIG. 7.

At block 1530, the method 1500 may include using the first uplinkscheduling or the second uplink scheduling based at least in part on acondition of the power management operation. The operation(s) at block1530 may be performed using the wireless communication managementcomponent 620, 720, 860, or 1084 described with reference to FIG. 6, 7,8, or 10, or the uplink scheduling management component 775 describedwith reference to FIG. 7.

At block 1535, the method 1500 may include scaling the total transmitpower on the first uplink component carrier to a reduced power for thecurrent subframe. The operation(s) at block 1535 may be performed usingthe wireless communication management component 620, 720, 860, or 1084described with reference to FIG. 6, 7, 8, or 10, the power managementcomponent 640 or 740 described with reference to FIG. 6 or 7, or theshared radio frequency spectrum band power management component 745and/or power scaling component 760 described with reference to FIG. 7.

At block 1540, the method 1500 may include using the first uplinkscheduling when the scaling does not surpass a threshold powerreduction, and using the second uplink scheduling when the scalingsurpasses the threshold power reduction. The operation(s) at block 1525may be performed using the wireless communication management component620, 720, 860, or 1084 described with reference to FIG. 6, 7, 8, or 10,or the uplink scheduling management component 775 described withreference to FIG. 7.

Thus, the method 1500 may provide for wireless communication. It shouldbe noted that the method 1500 is just one implementation and that theoperations of the method 1500 may be rearranged or otherwise modifiedsuch that other implementations are possible.

In some examples, aspects of one or more of the methods 1100, 1200,1300, 1400, or 1500 described with reference to FIG. 11, 12, 13, 14, or15 may be combined.

Techniques described herein may be used for various wirelesscommunications systems such as CDMA, TDMA, FDMA, OFDMA, SC-FDMA, andother systems. The terms “system” and “network” are often usedinterchangeably. A CDMA system may implement a radio technology such asCDMA2000, Universal Terrestrial Radio Access (UTRA), etc. CDMA2000covers IS-2000, IS-95, and IS-856 standards. IS-2000 Releases 0 and Aare commonly referred to as CDMA2000 1×, 1×, etc. IS-856 (TIA-856) iscommonly referred to as CDMA2000 1×EV-DO, High Rate Packet Data (HRPD),etc. UTRA includes Wideband CDMA (WCDMA) and other variants of CDMA. ATDMA system may implement a radio technology such as Global System forMobile Communications (GSM). An OFDMA system may implement a radiotechnology such as Ultra Mobile Broadband (UMB), Evolved UTRA (E-UTRA),IEEE 802.11 (Wi-Fi), IEEE 802.16 (WiMAX), IEEE 802.20, Flash-OFDM™, etc.UTRA and E-UTRA are part of Universal Mobile Telecommunication System(UMTS). 3GPP Long Term Evolution (LTE) and LTE-Advanced (LTE-A) are newreleases of UMTS that use E-UTRA. UTRA, E-UTRA, UMTS, LTE, LTE-A, andGSM are described in documents from an organization named “3rdGeneration Partnership Project” (3GPP). CDMA2000 and UMB are describedin documents from an organization named “3rd Generation PartnershipProject 2” (3GPP2). The techniques described herein may be used for thesystems and radio technologies mentioned above as well as other systemsand radio technologies, including cellular (e.g., LTE) communicationsover an unlicensed or shared bandwidth. The description above, however,describes an LTE/LTE-A system for purposes of example, and LTEterminology is used in much of the description above, although thetechniques are applicable beyond LTE/LTE-A applications.

The detailed description set forth above in connection with the appendeddrawings describes examples and does not represent all of the examplesthat may be implemented or that are within the scope of the claims. Theterms “example” and “exemplary,” when used in this description, mean“serving as an example, instance, or illustration,” and not “preferred”or “advantageous over other examples.” The detailed description includesspecific details for the purpose of providing an understanding of thedescribed techniques. These techniques, however, may be practicedwithout these specific details. In some instances, well-known structuresand apparatuses are shown in block diagram form in order to avoidobscuring the concepts of the described examples.

Information and signals may be represented using any of a variety ofdifferent technologies and techniques. For example, data, instructions,commands, information, signals, bits, symbols, and chips that may bereferenced throughout the above description may be represented byvoltages, currents, electromagnetic waves, magnetic fields or particles,optical fields or particles, or any combination thereof.

The various illustrative blocks and components described in connectionwith the disclosure herein may be implemented or performed with ageneral-purpose processor, a digital signal processor (DSP), an ASIC, anFPGA or other programmable logic device, discrete gate or transistorlogic, discrete hardware components, or any combination thereof designedto perform the functions described herein. A general-purpose processormay be a microprocessor, but in the alternative, the processor may beany conventional processor, controller, microcontroller, or statemachine. A processor may also be implemented as a combination ofcomputing devices, e.g., a combination of a DSP and a microprocessor,multiple microprocessors, one or more microprocessors in conjunctionwith a DSP core, or any other such configuration.

The functions described herein may be implemented in hardware, softwareexecuted by a processor, firmware, or any combination thereof. Ifimplemented in software executed by a processor, the functions may bestored on or transmitted over as one or more instructions or code on acomputer-readable medium. Other examples and implementations are withinthe scope and spirit of the disclosure and appended claims. For example,due to the nature of software, functions described above can beimplemented using software executed by a processor, hardware, firmware,hardwiring, or combinations of any of these. Features implementingfunctions may also be physically located at various positions, includingbeing distributed such that portions of functions are implemented atdifferent physical locations. As used herein, including in the claims,the term “or,” when used in a list of two or more items, means that anyone of the listed items can be employed by itself, or any combination oftwo or more of the listed items can be employed. For example, if acomposition is described as containing components A, B, or C, thecomposition can contain A alone; B alone; C alone; A and B incombination; A and C in combination; B and C in combination; or A, B,and C in combination. Also, as used herein, including in the claims,“or” as used in a list of items (for example, a list of items prefacedby a phrase such as “at least one of” or “one or more of”) indicates adisjunctive list such that, for example, a list of “at least one of A,B, or C” means A or B or C or AB or AC or BC or ABC (i.e., A and B andC).

Computer-readable media includes both computer storage media andcommunication media including any medium that facilitates transfer of acomputer program from one place to another. A storage medium may be anyavailable medium that can be accessed by a general purpose or specialpurpose computer. By way of example, and not limitation,computer-readable media can comprise RAM, ROM, EEPROM, flash memory,CD-ROM or other optical disk storage, magnetic disk storage or othermagnetic storage devices, or any other medium that can be used to carryor store desired program code means in the form of instructions or datastructures and that can be accessed by a general-purpose orspecial-purpose computer, or a general-purpose or special-purposeprocessor. Also, any connection is properly termed a computer-readablemedium. For example, if the software is transmitted from a website,server, or other remote source using a coaxial cable, fiber optic cable,twisted pair, digital subscriber line (DSL), or wireless technologiessuch as infrared, radio, and microwave, then the coaxial cable, fiberoptic cable, twisted pair, DSL, or wireless technologies such asinfrared, radio, and microwave are included in the definition of medium.Disk and disc, as used herein, include compact disc (CD), laser disc,optical disc, digital versatile disc (DVD), floppy disk and Blu-ray discwhere disks usually reproduce data magnetically, while discs reproducedata optically with lasers. Combinations of the above are also includedwithin the scope of computer-readable media.

The previous description of the disclosure is provided to enable aperson skilled in the art to make or use the disclosure. Variousmodifications to the disclosure will be readily apparent to thoseskilled in the art, and the generic principles defined herein may beapplied to other variations without departing from the scope of thedisclosure. Thus, the disclosure is not to be limited to the examplesand designs described herein but is to be accorded the broadest scopeconsistent with the principles and novel features disclosed herein.

What is claimed is:
 1. A method for wireless communication, comprising:identifying a first uplink component carrier of a plurality of componentcarriers configured for a user equipment (UE); determining that thefirst uplink component carrier is transmitted over an unlicensed radiofrequency spectrum band, wherein one or more devices contend to accessthe unlicensed radio frequency spectrum band; performing a transmitpower management operation on the first uplink component carrier, for acurrent subframe, based at least in part on the determining that thefirst uplink component carrier is transmitted over the unlicensed radiofrequency spectrum band, wherein the transmit power management operationincludes reducing a transmit power of the current subframe of the firstuplink component carrier; and carrying over the transmit powermanagement operation to at least one subsequent subframe following thecurrent subframe, wherein carrying over the transmit power managementoperation includes using the reduced transmit power for the at least onesubsequent subframe of the first uplink component carrier.
 2. The methodof claim 1, wherein performing the transmit power management operationcomprises: maintaining a transmit power on the first uplink componentcarrier at or above a minimum guaranteed power.
 3. The method of claim2, wherein the minimum guaranteed power depends on a channel type oruplink information type transmitted on the first uplink componentcarrier.
 4. The method of claim 3, further comprising: scheduling atleast one of a physical uplink control channel (PUCCH) or a physicaluplink shared channel (PUSCH) on the first uplink component carrierduring the current subframe.
 5. The method of claim 4, wherein theminimum guaranteed power comprises at least one of a PUCCH minimumguaranteed power component and a PUSCH minimum guaranteed powercomponent, and wherein the PUCCH minimum guaranteed power component isgreater than the PUSCH minimum guaranteed power component.
 6. The methodof claim 1, wherein the at least one subsequent subframe comprises atleast one uplink subframe between the current subframe and a boundary ofa subsequent frame.
 7. The method of claim 1, further comprising:dropping a transmission on the first uplink component carrier for atleast one of a number of uplink subframes between the current subframeand a boundary of a subsequent frame.
 8. The method of claim 1, whereinthe reducing surpasses a threshold power reduction, the method furthercomprising: dropping a transmission on the first uplink componentcarrier for at least one of a number of uplink subframes between thecurrent subframe and a boundary of a subsequent frame.
 9. The method ofclaim 1, wherein performing the transmit power management operationcomprises: dropping a transmission on the first uplink component carrierfor the current subframe.
 10. The method of claim 9, further comprising:dropping a transmission on the first uplink component carrier for atleast one of a number of uplink subframes between the current subframeand a boundary of a subsequent frame.
 11. The method of claim 9, furthercomprising: dropping a transmission on the first uplink componentcarrier for each of a number of uplink subframes between the currentsubframe and a boundary of a subsequent frame.
 12. The method of claim9, further comprising: performing a clear channel assessment (CCA) forthe unlicensed radio frequency spectrum band for at least one subsequentuplink subframe following the current subframe.
 13. The method of claim1, further comprising: receiving a first uplink scheduling for the firstuplink component carrier for the current subframe; and receiving asecond uplink scheduling for the first uplink component carrier for thecurrent subframe.
 14. The method of claim 13, further comprising: usingthe second uplink scheduling based at least in part on performing thetransmit power management operation.
 15. The method of claim 13, furthercomprising: using the first uplink scheduling or the second uplinkscheduling based at least in part on a condition of the transmit powermanagement operation.
 16. The method of claim 13, wherein performing thetransmit power management operation comprises: using the first uplinkscheduling when the reducing does not surpass a threshold powerreduction; and using the second uplink scheduling when the reducingsurpasses the threshold power reduction.
 17. The method of claim 1,wherein the plurality of component carriers comprises a second uplinkcomponent carrier transmitted over the unlicensed radio frequencyspectrum band.
 18. The method of claim 1, wherein the plurality ofcomponent carriers comprises a second uplink component carriertransmitted over a licensed radio frequency spectrum band.
 19. Themethod of claim 1, wherein the plurality of component carriers isconfigured for a carrier aggregation operation for the UE.
 20. Themethod of claim 1, wherein the plurality of component carriers isconfigured for a dual-connectivity operation for the UE.
 21. Anapparatus for wireless communication, comprising: means for identifyinga first uplink component carrier of a plurality of component carriersconfigured for a user equipment (UE); means for determining that thefirst uplink component carrier is transmitted over an unlicensed radiofrequency spectrum band, wherein one or more devices contend to accessthe unlicensed radio frequency spectrum band; means for performing atransmit power management operation on the first uplink componentcarrier, for a current subframe, based at least in part on thedetermining that the first uplink component carrier is transmitted overthe unlicensed radio frequency spectrum band, wherein the transmit powermanagement operation includes reducing a transmit power of the currentsubframe of the first uplink component carrier; and means for carryingover the transmit power management operation to at least one subsequentsubframe following the current subframe, wherein carrying over thetransmit power management operation includes using the reduced transmitpower for the at least one subsequent subframe of the first uplinkcomponent carrier.
 22. An apparatus for wireless communication,comprising: a processor; memory in electronic communication with theprocessor; and the processor and the memory configured to: identify afirst uplink component carrier of a plurality of component carriersconfigured for a user equipment (UE); determine that the first uplinkcomponent carrier is transmitted over an unlicensed radio frequencyspectrum band, wherein one or more devices contend to access theunlicensed radio frequency spectrum band; perform a transmit powermanagement operation on the first uplink component carrier, for acurrent subframe, based at least in part on the determining that thefirst uplink component carrier is transmitted over the unlicensed radiofrequency spectrum band, wherein the transmit power management operationincludes reducing a transmit power of the current subframe of the firstuplink component carrier; and carry over the transmit power managementoperation to at least one subsequent subframe following the currentsubframe, wherein carrying over the transmit power management operationincludes using the reduced transmit power for the at least onesubsequent subframe of the first uplink component carrier.
 23. Theapparatus of claim 22, wherein the processor and the memory areconfigured to: maintain a transmit power on the first uplink componentcarrier at or above a minimum guaranteed power.
 24. The apparatus ofclaim 23, wherein the minimum guaranteed power depends on a channel typeor uplink information type transmitted on the first uplink componentcarrier.
 25. The apparatus of claim 22, wherein the at least onesubsequent subframe comprises at least one uplink subframe between thecurrent subframe and a boundary of a subsequent frame.
 26. The apparatusof claim 22, wherein the reducing surpasses a threshold power reduction,the processor and memory further configured to: drop a transmission onthe first uplink component carrier for at least one of a number ofuplink subframes between the current subframe and a boundary of asubsequent frame.
 27. The apparatus of claim 22, wherein, for performingthe transmit power management operation, the processor and memory areconfigured to: drop a transmission on the first uplink component carrierfor the current subframe.
 28. The apparatus of claim 27, wherein theprocessor and memory are configured to: drop a transmission on the firstuplink component carrier for at least one of a number of uplinksubframes between the current subframe and a boundary of a subsequentframe.
 29. The apparatus of claim 27, wherein the processor and memoryare configured to: drop a transmission on the first uplink componentcarrier for each of a number of uplink subframes between the currentsubframe and a boundary of a subsequent frame.
 30. A non-transitorycomputer-readable medium storing computer-executable code for wirelesscommunication, the code executable by a processor to: identify a firstuplink component carrier of a plurality of component carriers configuredfor a user equipment (UE); determine that the first uplink componentcarrier is transmitted over an unlicensed radio frequency spectrum band,wherein one or more devices contend to access the unlicensed radiofrequency spectrum band; perform a transmit power management operationon the first uplink component carrier, for a current subframe, based atleast in part on the determining that the first uplink component carrieris transmitted over the unlicensed radio frequency spectrum band,wherein the transmit power management operation includes reducing atransmit power of the current subframe of the first uplink componentcarrier; and carry over the transmit power management operation to asubsequent subframe following the current subframe, wherein carryingover the transmit power management operation includes using the reducedtransmit power for the at least one subsequent subframe of the firstuplink component carrier.